Questions asked so far

solved Y Coordinate At X Sixteen A particle starts from the origin at t = 0 s with a velocity of 10.0 m/s along y and moves in the x-y plane with a co...
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solved X-Rays From Thirty Kilovolt Electrons X-rays are produced by 30 kV electrons. What is the maximum frequency of the X-rays, in Hz?
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solved Which Are Vectors Which of these are vectors?
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solved Where the Sun and the Earth Pull Alike A rocket is fired from the earth towards the sun. At what distance from the earth's centre is the gravitational force...
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solved When x Reaches Sixteen A particle starts from the origin at 10.0 m/s along y, and accelerates at 8.0 m/s² along x and 2.0 m/s² along y. At w...
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solved What a Force Is Made Of What is a force made of, when it moves a mass m through l in t?
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solved Weighing the Sun by the Earth How will you 'weigh the sun', that is estimate its mass? The mean orbital radius of the earth around the sun is 1.5 ×...
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solved Weighing the Earth by the Moon Weighing the Earth: the distance to the Moon is 3.84 × 10⁸ m and the time period of the Moon's revolution is 27.3 d. ...
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solved Weighing the Earth by Its Pull Weighing the Earth: you are given g = 9.81 m/s² at the Earth's surface and the Earth's radius 6.37 × 10⁶ m. What is t...
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solved Weighing Mars by Phobos The planet Mars has two moons, Phobos and Deimos. Phobos has a period of 7 hours, 39 minutes and an orbital radius of...
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solved Weighing Jupiter by Io Io, one of the satellites of Jupiter, has an orbital period of 1.769 d and the radius of the orbit is 4.22 × 10⁸ m. W...
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solved Refraction: Water to Air Light in water meets air at i. Which way does it bend coming out?
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solved Water Squeezed at Depth Taking the bulk modulus of water as 2.2 × 10⁹ N/m², what is the density of water at a depth where pressure is 80.0 at...
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solved Water Cooling Toward Its Surroundings A certain quantity of water cools from 70 °C to 60 °C in the first 5 min and to 54 °C in the next 5 min. The temperat...
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solved Warming Helium in a Cylinder A cylinder of fixed capacity 44.8 L contains helium gas at standard temperature and pressure. Taking R as 8.31 J mol⁻...
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solved The Volume of a Plate The same plate, 4.234 m by 1.005 m, is 2.01 cm thick. What is its volume, in cubic metres, to the figures the measure...
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solved Uranium Hexafluoride Isotopes Uranium has two isotopes of masses 235 g/mol and 238 g/mol. Both are present in uranium hexafluoride gas. If the atom...
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solved Under the Ceiling A ball is thrown at 40 m/s in a long hall whose ceiling is 25 m high. Taking g as 9.8 m/s², how far can it go without...
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solved Under an Overhead Power Line A horizontal overhead power line carries a current of 90 A in east to west direction. What is the magnitude of the ma...
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solved An Umbrella in the Rain Rain falls straight down at 35 m/s, and a wind then blows it sideways at 12 m/s. At what angle from the vertical shou...
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solved Two Ways from A to B In changing the state of a gas adiabatically from an equilibrium state A to another equilibrium state B, an amount of...
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solved Two Unit Vectors Added: Heading î and ĵ are unit vectors along x- and y- axis respectively. What angle does the vector î + ĵ make with the x-axis, in...
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solved Two Unit Vectors Added î and ĵ are unit vectors along x- and y- axis respectively. What is the magnitude of the vector î + ĵ?
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solved Two Syringes Joined Two syringes of different cross-sections (without needles) filled with water are connected with a tightly fitted rubb...
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solved Two Spheres Touched and Brought Closer A charged metallic sphere A is suspended by a nylon thread. Another charged metallic sphere B is brought close to A s...
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solved Two Small Spheres Thirty Centimetres Apart Two small charged spheres having charges of 2 × 10⁻⁷ C and 3 × 10⁻⁷ C are placed 30 cm apart in air. What is the forc...
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solved Two Sitar Strings Playing Ga Two sitar strings A and B playing the note ‘Ga’ are slightly out of tune and produce beats of frequency 6 Hz. The ten...
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solved Two Sitar Strings Two sitar strings A and B playing the note 'Dha' are slightly out of tune and produce beats of frequency 5 Hz. The te...
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solved Two Reacting Hydrogen Isotopes The Q value of a nuclear reaction A + b → C + d is defined by Q = [mA + mb – mC – md]c², where the masses refer to th...
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solved Two Points Three Quarters of a Wavelength Apart For the travelling harmonic wave y(x, t) = 2.0 cos 2π (10t – 0.0080 x + 0.35) where x and y are in cm and t in s, wha...
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solved Two Points Half a Wavelength Apart For the travelling harmonic wave y(x, t) = 2.0 cos 2π (10t – 0.0080 x + 0.35) where x and y are in cm and t in s, wha...
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solved Two Points Half a Metre Apart For the travelling harmonic wave y(x, t) = 2.0 cos 2π (10t – 0.0080 x + 0.35) where x and y are in cm and t in s, wha...
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solved Two Points Four Metres Apart For the travelling harmonic wave y(x, t) = 2.0 cos 2π (10t – 0.0080 x + 0.35) where x and y are in cm and t in s, wha...
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solved Two Parallel Wires Two long and parallel straight wires A and B carrying currents of 8.0 A and 5.0 A in the same direction are separated...
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solved Two Nuggets Apart The two gold nuggets weigh 20.17 g and 20.15 g. How many grams heavier is the one than the other?
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solved Two Deuterons Meeting What is the height of the potential barrier for a head on collision of two deuterons, in keV? (Hint: The height of th...
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solved Two Copper Spheres Fifty Centimetres Apart Two insulated charged copper spheres A and B have their centres separated by a distance of 50 cm, and the charge on e...
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solved Two Charges Apart Two charges of 7 μC and -2 μC are placed at (–9 cm, 0, 0) and (9 cm, 0, 0) respectively. What is the electrostatic po...
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solved Two Carbon Nuclei Fusing The Q value of a nuclear reaction A + b → C + d is defined by Q = [mA + mb – mC – md]c², where the masses refer to th...
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solved Two Billiard Balls Rebound Two billiard balls each of mass 0.05 kg moving in opposite directions with speed 6 m/s collide and rebound with the s...
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solved Twice as Fast to Stop Braking just as hard, how much farther does a car need to stop from twice the speed?
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solved Total Internal Reflection Light in a medium of index μ₁ meets one of μ₂ at i. How much turns back past the critical angle?
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solved A throw on the Moon A ball is thrown at 20 m/s, 45° above the ground, on the Moon. How far away does it land, in metres?
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solved Thrice the Escape Speed The escape speed of a projectile on the earth's surface is 11.2 km/s. A body is projected out with thrice this speed....
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solved A Three-Wheeler Stops A three-wheeler of 400 kg with its driver of 65 kg is doing 36 km/h when the driver sees a child in the road and brin...
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solved Three Capacitors in Series on 120 Volts Three capacitors each of capacitance 9 pF are connected in series. What is the potential difference across each capac...
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solved Three Capacitors in Series Three capacitors each of capacitance 9 pF are connected in series. What is the total capacitance of the combination, ...
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solved Three Capacitors in Parallel Three capacitors of capacitances 2 pF, 3 pF and 4 pF are connected in parallel. What is the total capacitance of the ...
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solved There and Back: Velocity A man walks 2.5 km to a market in 30 min, finds it shut, and walks straight home in 20 min. What is the size of his a...
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solved There and Back: Speed A man walks 2.5 km to a market in 30 min, finds it shut, and walks straight home in 20 min. What is his average speed...
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solved The Work of a Steady Push A body of mass 2 kg initially at rest moves under the action of an applied horizontal force of 7 N on a table with co...
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solved The Work Friction Takes A body of mass 2 kg initially at rest moves under the action of an applied horizontal force of 7 N on a table with co...
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solved The Two Scalars Which two of these are scalars?
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solved The Speed of Sound in Air The mass of 1 mole of air is 29.0 × 10⁻³ kg/mol. Taking the ratio of specific heats of air as 1.4, what is the speed ...
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solved The Specific Heat of a Metal In an experiment on the specific heat of a metal, a 0.20 kg block of the metal at 150 °C is dropped in a copper calor...
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solved The Shortest X-Rays From Thirty Kilovolts X-rays are produced by 30 kV electrons. What is the minimum wavelength of the X-rays, in nm?
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solved The Second Orbit of Hydrogen The radius of the innermost electron orbit of a hydrogen atom is 5.3 × 10⁻¹¹ m. What is the radius of the n = 2 orbit...
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solved The Same Error Twice Two masses, 1.02 g and 9.89 g, are each weighed to within 0.01 g. What is the relative error in the lighter one?
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solved The Resistor on a Ten Volt Battery A battery of emf 10 V and internal resistance 3 Ω is connected to a resistor. If the current in the circuit is 0.5 A,...
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solved The Resistivity of a Wire A negligibly small current is passed through a wire of length 15 m and uniform cross-section 6.0 × 10⁻⁷ m², and its r...
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solved The Pressure on the Thighbones The two thigh bones (femurs), each of cross-sectional area 10 cm², support the upper part of a human body of mass 40 ...
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solved The Power of a Lens If f = 0.5 m for a glass lens, what is the power of the lens, in dioptres?
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solved The Only Vector Which one of these is a vector?
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solved The Net Work on a Pushed Body A body of mass 2 kg initially at rest moves under the action of an applied horizontal force of 7 N on a table with co...
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solved The Needle's Magnification A 4.5 cm needle is placed 12 cm away from a convex mirror of focal length 15 cm. What is the magnification?
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solved The Most Precise Instrument Which of these can measure a length most precisely?
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solved The Moon Through a Giant Telescope A giant refracting telescope at an observatory has an objective lens of focal length 15 m. The telescope is used to v...
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solved The Moon's Month Kepler's constant for orbits round the Earth is k = 1 × 10⁻¹³ s²/m³, so that T² = kR³. The Moon is at a distance of 3...
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solved The Missing c In units where light's speed c is 1, a moving body's mass is written m = m₀ ⁄ √(1 − v²). Put c back. Which is right?
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solved The Magnetic Side of a Wave A plane electromagnetic wave of frequency 25 MHz travels in free space along the x-direction. At a particular point i...
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solved The Long Way Round: Velocity A hotel is 10 km from the station along a straight road, but a dishonest driver takes a 23 km route and gets there in...
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solved The Long Way Round: Speed A hotel is 10 km from the station along a straight road, but a dishonest driver takes a 23 km route and gets there in...
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solved The Larger Piston Moves Out Two syringes of different cross-sections (without needles) filled with water are connected with a tightly fitted rubb...
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solved The Inductor's Drop at Resonance A series LCR circuit is connected to a variable frequency 230 V source, with L = 5.0 H, C = 80 μF and R = 40 Ω. The s...
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solved The Image in a Concave Lens An object of size 3.0 cm is placed 14 cm in front of a concave lens of focal length 21 cm. What is the size of the im...
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solved The Hydrogen Atom's Size It is found experimentally that 13.6 eV of energy is required to separate a hydrogen atom into a proton and an electr...
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solved The Heat of Aluminium A sphere of 0.047 kg aluminium is placed for sufficient time in a vessel containing boiling water, so that the sphere...
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solved The Ground State's Potential Energy The ground state energy of hydrogen atom is -13.6 eV. What is the potential energy of the electron in this state, in eV?
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solved The Glass of a Double Convex Lens The radii of curvature of the faces of a double convex lens are 10 cm and 15 cm. Its focal length is 12 cm. What is t...
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solved The Flux Leaving a Charged Sphere A uniformly charged conducting sphere of 2.4 m diameter has a surface charge density of 80.0 μC/m². What is the total...
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solved The Field Midway Between Two Charges Two point charges qA = 3 μC and qB = -3 μC are located 20 cm apart in vacuum. What is the electric field at the midpo...
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solved The Fastest Whirl A stone of mass 0.25 kg tied to the end of a string is whirled round in a circle of radius 1.5 m in a horizontal plan...
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solved The Excess Pressure in a Mercury Drop A drop of mercury has a radius of 3.00 mm at room temperature. Surface tension of mercury at that temperature (20 °C)...
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solved The Energy in a Gram What is the energy equivalent of 1 g of substance, in joules?
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solved The Emitter of an Argon Laser Light of wavelength 488 nm is produced by an argon laser which is used in the photoelectric effect. When light from t...
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solved The Electron's Speed in the First Level Using the Bohr's model, calculate the speed of the electron in a hydrogen atom in the n = 1 level, in m/s?
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solved The Electron's Speed in Hydrogen It is found experimentally that 13.6 eV of energy is required to separate a hydrogen atom into a proton and an electr...
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solved The Electron's Frequency of Revolution In a chamber, a uniform magnetic field of 6.5 G is maintained. An electron is shot into the field with a speed of 4.8...
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solved The Electric Side of a Wave The amplitude of the magnetic field part of a harmonic electromagnetic wave in vacuum is B₀ = 510 nT. What is the amp...
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solved The Earth's Quantum Number In accordance with the Bohr's model, what is the quantum number that characterises the earth's revolution around the ...
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solved The Drunkard's Walk A drunkard in a narrow lane takes 5 steps forward and 3 back, again and again, each step 1 m long and 1 s long. How l...
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solved The Density of an Iron Nucleus Given the mass of iron nucleus as 55.85 u and A = 56, and taking R₀ as 1.2 fm, what is the nuclear density, in kg/m³?
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solved The Current Amplitude at Resonance A series LCR circuit is connected to a variable frequency 230 V source, with L = 5.0 H, C = 80 μF and R = 40 Ω. The s...
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solved The Conduction Current into a Capacitor A parallel plate capacitor made of circular plates each of radius R = 6.0 cm has a capacitance C = 100 pF. The capaci...
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solved The Charge on Each Plate In a parallel plate capacitor with air between the plates, each plate has an area of 6 × 10⁻³ m² and the distance bet...
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solved The Charge on a Charged Sphere A uniformly charged conducting sphere of 2.4 m diameter has a surface charge density of 80.0 μC/m². Find the charge o...
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solved The Charge on a Capacitor in Parallel Three capacitors of capacitances 2 pF, 3 pF and 4 pF are connected in parallel, and the combination is connected to a...
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solved The Charge Behind a Flux A point charge causes an electric flux of -1.0 × 10³ N m²/C to pass through a spherical Gaussian surface of 10.0 cm r...
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solved The Centre of a Charged Hexagon A regular hexagon of side 10 cm has a charge 5 μC at each of its vertices. Calculate the potential at the centre of t...
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solved The Capacitor's Drop at Resonance A series LCR circuit is connected to a variable frequency 230 V source, with L = 5.0 H, C = 80 μF and R = 40 Ω. The s...
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solved The Candle's Image A small candle, 2.5 cm in size is placed at 27 cm in front of a concave mirror of radius of curvature 36 cm. A screen...
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solved The Bottom of the Ocean The average depth of the Indian Ocean is about 3000 m. Given that the bulk modulus of water is 2.2 × 10⁹ N/m² and tak...
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solved Sunlight on Its Way Suppose the unit of length were the distance light goes in one second. Sunlight takes 8 minutes 20 seconds to reach u...
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solved Stopped by a Steady Force A body of 20 kg is moving at 15 m/s when a steady force of 50 N starts to act against its motion. How long does it ta...
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solved Steam Passed Into Water Till Ninety Steam is passed into 54 g of water at 30 °C till the temperature of the mixture becomes 90 °C. If the latent heat of ...
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solved Splitting an Iron Nucleus Suppose, we think of fission of an iron nucleus, ⁵⁶₂₆Fe, into two equal fragments, ²⁸₁₃Al. Given m(⁵⁶₂₆Fe) = 55.93494...
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solved Speed When x Reaches Sixteen A particle starts from the origin at 10.0 m/s along y, and accelerates at 8.0 m/s² along x and 2.0 m/s² along y. How ...
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solved Speed from a Path A particle's position is r = 3.0t î + 2.0t² ĵ + 5.0 k̂ metres, with t in seconds. How fast is it moving at t = 1.0 s,...
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solved Speed at Two Seconds A particle's position is r = 3.0t î − 2.0t² ĵ + 4.0 k̂ metres, with t in seconds. How fast is it moving at t = 2.0 s,...
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solved Speed at Eighty-Four A particle starts from the origin at 5.0 m/s along x, and accelerates at 3.0 m/s² along x and 2.0 m/s² along y. How f...
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solved The Skin of a Cube Each edge of a cube is measured as 7.203 m. What is its total surface area, in square metres, to as many significant ...
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solved The Skin of a Can A closed can is a cylinder of radius 2.0 cm and height 10.0 cm. What is its whole surface area, in square metres?
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solved Sharing a Charge A 900 pF capacitor is charged by a 100 V battery. It is disconnected from the battery and connected to another unchar...
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solved A Share of the Sky How much of the sky does a patch of area A cover, seen from r away?
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solved Ruled Out by Dimensions A body of mass m moves at speed v with acceleration a. Which of these could be its kinetic energy K? Dimensions rule ...
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solved Round the Groove An insect trapped in a circular groove of radius 12 cm goes round it steadily, 7 times in 100 s. What is its angular ...
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solved Room in a Mole A mole of hydrogen gas fills about 22.4 litres at room pressure and 0 °C. Take a hydrogen atom to be a ball of radius...
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solved RMS Speed Doubled From the Ice Point The temperature at which the RMS velocity of the gas molecules would become twice of its value at 0 °C is
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solved Riding on a Speeding Train A stone of mass 0.1 kg is lying on the floor of a train which is accelerating with 1 m/s², the stone being at rest re...
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solved Relative Refractive Index Light meets a medium of index μ₂ at 30°, and the two media's relative index is μ₂₁. Do both numbers matter, or only w...
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solved Refractive Index Light passes from a medium of index μ₁ into one of μ₂ at 30°. Where does the bending come from?
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solved Refraction: Air to Water Where does a ray go when it passes from air into water at i?
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solved Reflection Where does a ray go when it hits a mirror at i?
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solved Reflectance Light meets a surface between indices μ₁ and μ₂ at i. How much of it gets through?
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solved Radians in an Arc An arc 0.5 m long is cut from a circle of radius 2 m. What angle does it make at the centre, in radians?
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solved Pushed Two Ways A body of 5 kg is pushed by two forces at right angles to each other, 8 N and 6 N. How strongly does it accelerate, i...
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solved Pushed Back, Then Left Alone A body of mass 0.40 kg moving initially with a constant speed of 10 m/s to the north is subject to a constant force o...
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solved Pushed Back for Twenty-Five Seconds A body of mass 0.40 kg moving initially with a constant speed of 10 m/s to the north is subject to a constant force o...
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solved Pulling the Lighter Body Two bodies A and B of masses 10 kg and 20 kg respectively kept on a smooth, horizontal surface are tied to the ends o...
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solved Pulling the Heavier Body Two bodies A and B of masses 10 kg and 20 kg respectively kept on a smooth, horizontal surface are tied to the ends o...
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solved Pulled Round the Groove An insect trapped in a circular groove of radius 12 cm goes round it steadily, 7 times in 100 s. What is its accelera...
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solved Projectile A body is thrown at v(u₀) at θ(u₀) where gravity is g. Where does it land, how high does it go, and how long is it in...
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solved Polythene Rubbed with Wool A polythene piece rubbed with wool is found to have a negative charge of 3 × 10⁻⁷ C. Estimate the number of electrons...
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solved Photons from a Laser Monochromatic light of frequency 6.0 × 10¹⁴ Hz is produced by a laser. The power emitted is 2.0 × 10⁻³ W. How many ph...
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solved Photons From a Helium-Neon Laser Monochromatic light of wavelength 632.8 nm is produced by a helium-neon laser. The power emitted is 9.42 mW. How many...
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solved A Pendulum by Dimensions A pendulum of length l and bob of mass m swings where gravity is g. How does its period depend on what it is made of?
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solved Pedalling a Generator Kamla peddles a stationary bicycle. The pedals of the bicycle are attached to a 100 turn coil of area 0.10 m². The co...
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solved Pascal's Wine Barometer Toricelli's barometer used mercury. Pascal duplicated it using French wine of density 984 kg/m³. Taking g as 9.8 m/s²...
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solved Oxygen Molecules in Their Gas Take the diameter of an oxygen molecule to be 3 Å. Estimate the fraction of molecular volume to the actual volume occ...
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solved Oxygen Drawn from a Cylinder An oxygen cylinder of volume 30 L has an initial gauge pressure of 15 atm and a temperature of 27 °C. After some oxyg...
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solved Out of water at 60° Light in water meets the surface with air at 60° to the normal. Which are true?
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solved One Atomic Mass Unit What is the energy equivalent of 1 u, in MeV?
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solved Off a Cliff A hiker at the edge of a cliff 490 m high throws a stone horizontally at 15 m/s. Taking g as 9.8 m/s², how long does ...
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solved Neon and Oxygen in a Vessel A vessel contains two non-reactive gases: neon (monatomic) and oxygen (diatomic). The ratio of their partial pressure...
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solved Neon and Oxygen by Density A vessel contains two non-reactive gases: neon (monatomic) and oxygen (diatomic). The ratio of their partial pressure...
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solved Near a Long Straight Wire A long straight wire carries a current of 35 A. What is the magnitude of the field B at a point 20 cm from the wire, ...
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solved Instants of a Projectile A body is thrown at v(thrown) at θ(thrown) where gravity is g. Where does it land, how high does it go, and how long ...
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solved Molar Volume at STP Molar volume is the volume occupied by 1 mol of any (ideal) gas at standard temperature and pressure (STP : 1 atmosph...
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solved Mica Slid In with the Supply Connected In a parallel plate capacitor with air between the plates, each plate has an area of 6 × 10⁻³ m² and the distance bet...
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solved Mica Slid In After Disconnecting In a parallel plate capacitor with air between the plates, each plate has an area of 6 × 10⁻³ m² and the distance bet...
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solved Melting Ice in Warm Water When 0.15 kg of ice at 0 °C is mixed with 0.30 kg of water at 50 °C in a container, the resulting temperature is 6.7 ...
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solved Landing off a Cliff A hiker at the edge of a cliff 490 m high throws a stone horizontally at 15 m/s. Taking g as 9.8 m/s², how fast is it...
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solved Just Outside a Charged Sphere A spherical conductor of radius 12 cm has a charge of 1.6 × 10⁻⁷ C distributed uniformly on its surface. What is the ...
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solved Iron and Brass End to End An iron bar (length 0.1 m, cross-section 0.02 m², thermal conductivity 79 W m⁻¹ K⁻¹) and a brass bar (length 0.1 m, c...
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solved Into Air Light leaves a medium of index μ₁ for air at 30°. Does every medium have its own angle?
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solved Internal Reflection Light in water meets air at i. What happens to the light that is not refracted?
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solved Inside a Solenoid A solenoid of length 0.5 m has a radius of 1 cm and is made up of 500 turns. It carries a current of 5 A. What is the...
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solved Inside a Drop of Mercury A drop of mercury has a radius of 3.00 mm at room temperature. Surface tension of mercury at that temperature (20 °C)...
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solved Incidence What is there to measure when a ray hits a surface at i?
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solved Ice to Steam Calculate the heat required to convert 3 kg of ice at -12 °C kept in a calorimeter to steam at 100 °C at atmospheric ...
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solved Hydrogen to Match Oxygen's PV/T Plots of PV/T versus P are drawn for 1.00 × 10⁻³ kg of oxygen gas at two different temperatures. The molecular mass o...
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solved Hydrogen Squeezed Under Sand A cylinder with a movable piston contains 3 moles of hydrogen at standard temperature and pressure. The walls of the ...
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solved How Soon a Stone Reaches Fifteen Metres A stone is thrown straight up at 20 m/s. Taking g as 10 m/s², how many seconds after the throw does it reach 15 m abo...
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solved How Long to Stop A car doing 126 km/h brakes steadily and comes to rest in 200 m. How long does it take to stop, in seconds?
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solved How High the Air Goes The density of the atmosphere at sea level is 1.29 kg/m³. Assume that it does not change with altitude. Taking g as 9...
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solved How High It Goes A ball is thrown straight up at 29.4 m/s. Taking g as 9.8 m/s², how high does it rise, in metres?
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solved How Far Saturn Is A saturn year is 29.5 times the earth year. How far is the saturn from the sun if the earth is 1.50 × 10⁸ km away fro...
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solved How Far Apart the Spheres Are The electrostatic force on a small sphere of charge 0.4 μC due to another small sphere of charge –0.8 μC in air is 0....
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solved Hot Water Cooling From Sixty Hot water cools from 60 °C to 50 °C in the first 10 min and to 42 °C in the next 10 min. Then the temperature of the ...
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solved Height at Eighty-Four A particle starts from the origin at 5.0 m/s along x, and accelerates at 3.0 m/s² along x and 2.0 m/s² along y. What ...
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solved Heavier than Water Lead is 11.3 times as dense as water, and water is 1000 kg per cubic metre. What is the density of lead, in kilograms...
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solved Heading at Two Seconds The position of a particle is given by r = 3.0t î − 2.0t² ĵ + 4.0 k̂ m, where t is in seconds and the coefficients ha...
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solved Heading across the Current A motorboat heads north at 25 km/h through a current that flows at 10 km/h toward 60° east of south. How many degrees...
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solved Gravitation in Grams The gravitational constant G is 6.67 × 10⁻¹¹ N m² kg⁻². What is it in cm³ g⁻¹ s⁻²?
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solved Gold and Silver Nuclei What is approximately the ratio of the nuclear radii of the gold isotope (A = 197) and the silver isotope (A = 107)?
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solved Galileo's Odd Numbers A body falls from rest. In successive equal intervals of time, the distances it falls are in the ratio
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solved Free Oscillations of an LC Circuit A charged 30 μF capacitor is connected to a 27 mH inductor. What is the angular frequency of free oscillations of the...
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solved Four Hollow Columns Four identical hollow cylindrical columns of mild steel support a big structure of mass 50000 kg. The inner and outer...
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solved Four Capacitors on 500 Volts A network of four 10 μF capacitors is connected to a 500 V supply: three of them in series, and the fourth across tha...
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solved Forty Minutes Out: Velocity A man walks on a straight road from his home to a market 2.5 km away with a speed of 5 km/h. Finding the market close...
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solved Forty Minutes Out: Speed A man walks on a straight road from his home to a market 2.5 km away with a speed of 5 km/h. Finding the market close...
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solved Flux Through a Square Consider a uniform electric field E = 3 × 10³ N/C along x. What is the flux of this field through a square of 10 cm o...
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solved Flux out of a Black Box Careful measurement of the electric field at the surface of a black box indicates that the net outward flux through t...
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solved Five Millihenries Twenty Microfarads And A Hundred Twenty Ohms Resonating An L-C-R series circuit with L = 5 mH, C = 20 μF, R = 120 Ω is connected to an AC source. The resonant frequency of t...
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solved First at Half the Amplitude A particle moves in simple harmonic motion with amplitude 10 cm and period 2 s. It is released from rest at its posit...
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solved Figures that Count Which of these are written to four significant figures?
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solved Fifty Grams Of Ice In Water At Eighty 50 g of ice at 0 °C is mixed with 50 g of water at 80 °C, final temperature of mixture will be
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solved Fifteen Metres Up on the Way Down A stone is thrown straight up at 20 m/s. Taking g as 10 m/s², how many seconds after the throw is it 15 m above the p...
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solved Errors in a Product How sure can we be of the product of a ± Δa and b ± Δb?
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solved Electrons Drifting in Copper A copper wire of cross-sectional area 1.0 × 10⁻⁷ m² carries a current of 1.5 A. Assume that each copper atom contribu...
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solved Eighteen Centimetres from a Charged Sphere A spherical conductor of radius 12 cm has a charge of 1.6 × 10⁻⁷ C distributed uniformly on its surface. What is the ...
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solved East of a Wire Running South A long straight wire in the horizontal plane carries a current of 50 A in north to south direction. What is the magni...
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solved Dropped From a Truck: Heading A truck starts from rest and accelerates uniformly at 2.0 m/s². At t = 10 s, a stone is dropped by a person standing ...
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solved Dropped From a Truck A truck starts from rest and accelerates uniformly at 2.0 m/s². At t = 10 s, a stone is dropped by a person standing ...
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solved Dropped From a Speeding Train A stone of mass 0.1 kg is dropped from the window of a train accelerating with 1 m/s². Neglect air resistance, and ta...
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solved Double-Convex Lenses of One Radius Double-convex lenses are to be manufactured from a glass of refractive index 1.55, with both faces of the same radius...
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solved Doping Silicon with Arsenic Suppose a pure Si crystal has 5 × 10²⁸ m⁻³ atoms. It is doped by 1 × 10⁻⁶ concentration of pentavalent As. Given that...
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solved Dipoles Turning in a Field A molecule of a substance has a permanent electric dipole moment of magnitude 10⁻²⁹ C m. A mole of this substance, wi...
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solved The Dimensions of Density What are the dimensions of density?
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solved The Density of the Sun The Sun has a mass of about 2.0 × 10³⁰ kg and a radius of about 7.0 × 10⁸ m. What is its average density, in kilogram...
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solved Critical Angle Light in water meets air at i. At what angle does it stop getting out?
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solved Copper Spheres Doubled and Halved Two insulated charged copper spheres A and B have their centres separated by a distance of 50 cm, and the charge on e...
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solved Copper and Steel End to End A copper wire of length 2.2 m and a steel wire of length 1.6 m, both of diameter 3.0 mm, are connected end to end. Wh...
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solved Catching a Ruler A friend lets go of a ruler held between your fingers, and you catch it after it has fallen 21.0 cm. Taking g as 9.8 ...
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solved Caesium Stopped at 0.60 V The work function of caesium is 2.14 eV. What is the wavelength of the incident light if the photocurrent is brought ...
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solved Caesium's Threshold The work function of caesium is 2.14 eV. What is the threshold frequency for caesium, in hertz?
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solved Caesium's Stopping Potential The work function of caesium metal is 2.14 eV. When light of frequency 6 × 10¹⁴ Hz is incident on the metal surface, ...
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solved Caesium's Fastest Photoelectrons The work function of caesium metal is 2.14 eV. When light of frequency 6 × 10¹⁴ Hz is incident on the metal surface, ...
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solved Bringing In a Charge A charge of 4 × 10⁻⁷ C is located 9 cm from a point P. What is the work done in bringing a charge of 2 × 10⁻⁹ C from ...
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solved Braking to a Stop A car doing 126 km/h brakes steadily and comes to rest in 200 m. What is its acceleration, in m/s²?
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solved Both Times a Ball Passes a Ledge A ball is thrown straight up at 20 m/s from the foot of a wall with a ledge 15 m up it. Taking g as 9.8 m/s², at what...
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solved Blowing a Bubble Under Water The lower end of a capillary tube of diameter 2.00 mm is dipped 8.00 cm below the surface of water in a beaker. The s...
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solved Between Two Crests A transverse harmonic wave on a string is described by y(x, t) = 3.0 sin (36 t + 0.018 x + π/4) where x and y are in ...
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solved Between Two Charged Plates Two large, thin metal plates are parallel and close to each other. On their inner faces, the plates have surface char...
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solved Bending at 40° Light in air meets water at 40° to the normal. What is the angle of refraction?
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solved Before the Push Back A body of mass 0.40 kg moving initially with a constant speed of 10 m/s to the north is subject to a constant force o...
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solved Back in the Hands A ball is thrown straight up at 29.4 m/s. Taking g as 9.8 m/s², after how many seconds is it back in the thrower's ha...
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solved At the Top of a Throw A ball thrown straight up is at its highest point. Which are true?
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solved As High as It Goes Far A cricketer can throw a ball at most 100 m. How high can they throw the same ball, in metres?
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solved Argon as Fast as Cold Helium The atomic mass of Ar is 39.9 g/mol and of He is 4.0 g/mol. At what temperature is the root mean square speed of an a...
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solved Argon and Chlorine in a Flask A flask contains argon and chlorine in the ratio of 2:1 by mass. The temperature of the mixture is 27 °C. The atomic ...
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solved The Area of a Sheet A sheet is measured as 16.2 ± 0.1 cm long and 10.1 ± 0.1 cm wide. Its area is about 163.6 cm². To within how many squ...
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solved The Area of a Plate A metal plate is 4.234 m long and 1.005 m wide. What is its area, in square metres, to the figures the measurements a...
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solved Any Two Media A ray meets the boundary between two media, of indices μ₁ and μ₂, at 20°. What do they do to it?
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solved An Angle from an Arc How big is an angle whose arc is s long on a circle of radius r?
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solved An Unknown Gas Weighed by Its Density The density of an unknown gas at 97 °C and 0.95 atm is 2.5 g/litre. Assuming the gas to be an ideal one, the molecula...
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solved An Ultrasonic Scanner A hospital uses an ultrasonic scanner to locate tumours in a tissue. The operating frequency of the scanner is 4.2 MH...
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solved An Oscillator's Amplitude from Its Start The motion of a particle executing simple harmonic motion is described by the displacement function, x(t) = A cos (ωt...
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solved An Object Before a Concave Mirror An object is placed 10 cm in front of a concave mirror of radius of curvature 15 cm. Where is the image, in cm, measu...
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solved An Object Before a Concave Lens An object of size 3.0 cm is placed 14 cm in front of a concave lens of focal length 21 cm. Where is the image, in cm,...
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solved An Object at 140 °F If temperature of an object is 140 °F, then its temperature in centigrade is
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solved An LCR Circuit's Power A sinusoidal voltage of peak value 283 V and frequency 50 Hz is applied to a series LCR circuit in which R = 3 Ω, L =...
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solved An LCR Circuit's Phase A sinusoidal voltage of peak value 283 V and frequency 50 Hz is applied to a series LCR circuit in which R = 3 Ω, L =...
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solved An LCR Circuit at Resonance A series LCR circuit has R = 3 Ω, L = 25.48 mH and C = 796 μF. The frequency of its sinusoidal source can be varied. ...
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solved An LCR Circuit at Its Natural Frequency A series LCR circuit with R = 20 Ω, L = 1.5 H and C = 35 μF is connected to a variable-frequency 200 V ac supply. Whe...
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solved An Iron Ring on a Wheel A blacksmith fixes an iron ring on the rim of the wooden wheel of a horse cart. The diameter of the rim and the iron ...
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solved An Iron Nucleus's Binding Energy What is the binding energy of the nucleus of iron (A = 56, Z = 26), given its mass 55.934939 u, with mH = 1.007825 u ...
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solved An Iron Core's Magnetising Current A solenoid has a core of a material with relative permeability 400. The windings of the solenoid are insulated from t...
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solved An Iron Core's Magnetisation A solenoid has a core of a material with relative permeability 400. The windings of the solenoid are insulated from t...
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solved An Infinite Line Charge An infinite line charge produces a field of 9 × 10⁴ N/C at a distance of 2 cm. Calculate the linear charge density, i...
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solved An Inductor on an AC Supply A 44 mH inductor is connected to 220 V, 50 Hz ac supply. What is the rms value of the current in the circuit, in ampe...
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solved An Elevator's Motor An elevator can carry a maximum load of 1800 kg (elevator + passengers) and is moving up with a constant speed of 2 m...
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solved An Electron Shot into a Chamber In a chamber, a uniform magnetic field of 6.5 G is maintained. An electron is shot into the field with a speed of 4.8...
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solved An Electron's Wavelength An electron of mass 9.11 × 10⁻³¹ kg moves with a speed of 5.4 × 10⁶ m/s. What is the de Broglie wavelength associated...
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solved An Electron Pulled by a Proton An electron and a proton are 1 × 10⁻¹⁰ m apart. Taking the charge of an electron as -1.6 × 10⁻¹⁹ C and its mass as 9....
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solved An Electron Falls in a Field An electron falls from rest through a distance of 1.5 cm in a uniform electric field of magnitude 2.0 × 10⁴ N/C. Taki...
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solved An Electron Drifting Three Metres The number density of free electrons in a copper conductor is 8.5 × 10²⁸ m⁻³. A wire 3.0 m long has an area of cross-...
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solved An Electron Circling in a Field An electron (mass 9 × 10⁻³¹ kg, charge 1.6 × 10⁻¹⁹ C) is moving with a speed of 3 × 10⁷ m/s in a magnetic field of 6 ...
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solved An Astronaut Adrift An astronaut accidentally gets separated out of his small spaceship accelerating in interstellar space at a constant ...
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solved An Aluminium Cube Sheared The edge of an aluminium cube is 10 cm long. One face of the cube is firmly fixed to a vertical wall. A mass of 100 k...
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solved An α-Particle Turned Back In a Geiger-Marsden experiment, a 7.7 MeV α-particle heads straight for a gold nucleus (Z = 79). What is its distance...
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solved An Air Bubble in Soap Solution An air bubble of radius 5.00 mm is formed at depth of 40.0 cm inside a container containing soap solution (of relativ...
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solved An AC Supply's RMS Voltage The peak voltage of an ac supply is 300 V. What is the rms voltage, in volts?
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solved An AC Circuit's Peak Current The rms value of current in an ac circuit is 10 A. What is the peak current, in amperes?
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solved Along a Straight Line A body starts at the origin with velocity v₀ and speeds up or slows down steadily at a. Where is it after t, and how ...
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solved Air Squeezed Without Heat Air at 1 atm fills 8 L of a diesel engine's cylinder. It is compressed so fast that no heat escapes, until its pressu...
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solved Air Shared With an Evacuated Vessel A vessel containing 0.1 m³ of air at 76 cm of Hg is connected to an evacuated vessel of capacity 0.09 m³. The resulta...
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solved Air Molecules in a Room Estimate the total number of air molecules (inclusive of oxygen, nitrogen, water vapour and other constituents) in a ...
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solved Across the Current A motorboat heads north at 25 km/h through a current that flows at 10 km/h toward 60° east of south. How fast does it...
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solved Acceleration in Kilometres A car speeds up at 3.0 m/s². What is that in kilometres per hour per hour?
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solved A Wire's Tension in Its Fundamental Mode A wire stretched between two rigid supports vibrates in its fundamental mode with a frequency of 45 Hz. The mass of t...
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solved A Wire Inside a Solenoid A 3.0 cm wire carrying a current of 10 A is placed inside a solenoid perpendicular to its axis. The magnetic field in...
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solved A Wire in Its Fundamental Mode A wire stretched between two rigid supports vibrates in its fundamental mode with a frequency of 45 Hz. The mass of t...
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solved A Wire Held Up by a Field A straight wire of mass 200 g and length 1.5 m carries a current of 2 A. It is suspended in mid-air by a uniform hori...
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solved A Wire at Thirty Degrees to a Field What is the magnitude of magnetic force per unit length on a wire carrying a current of 8 A and making an angle of 30...
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solved A Whirled Stone's String A stone of mass 0.25 kg tied to the end of a string is whirled round in a circle of radius 1.5 m with a speed of 40 r...
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solved A Wheel Slipped on a Shaft A large steel wheel is to be fitted on to a shaft of the same material. At 27 °C, the outer diameter of the shaft is ...
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solved A Wheel's Spokes A wheel with 10 metallic spokes each 0.5 m long is rotated with a speed of 120 rpm in a plane normal to the horizonta...
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solved A Wave Travelling along Z A plane electromagnetic wave travels in vacuum along z-direction. If the frequency of the wave is 30 MHz, what is its...
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solved A Wave from Its Equation The magnetic field in a plane electromagnetic wave is given by B_y = (2 × 10⁻⁷ T) sin(0.5 × 10³ rad/m x + 1.5 × 10¹¹ ...
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solved A Wave Along a String A wave travelling along a string is described by y(x, t) = 0.005 sin(80.0 x – 3.0 t), in which the numerical constant...
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solved A Variable Source Tuned to Resonance A series LCR circuit is connected to a variable frequency 230 V source, with L = 5.0 H, C = 80 μF and R = 40 Ω. What ...
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solved A Twelve Picofarad Capacitor A 12 pF capacitor is connected to a 50 V battery. How much electrostatic energy is stored in the capacitor, in joules?
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solved A Tumbling Oxygen Molecule The oxygen molecule has a mass of 5.30 × 10⁻²⁶ kg and a moment of inertia of 1.94 × 10⁻⁴⁶ kg m² about an axis through...
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solved A Tube with a Movable Piston A metre-long tube open at one end, with a movable piston at the other end, shows resonance with a fixed frequency sou...
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solved A Tower Through a Small Telescope A small telescope has an objective lens of focal length 140 cm. The telescope is used to view a 100 m tall tower 3 km...
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solved A Toaster's Element An electric toaster uses nichrome for its heating element. When a negligibly small current passes through it, its res...
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solved A Test Charge at the Midpoint Two point charges qA = 3 μC and qB = -3 μC are located 20 cm apart in vacuum. A negative test charge of magnitude 1.5...
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solved A Ten Volt Battery's Terminal Voltage A battery of emf 10 V and internal resistance 3 Ω is connected to a resistor. If the current in the circuit is 0.5 A,...
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solved A Swimmer Under a Lake A swimmer is 10 m below the surface of a lake. Taking the density of water as 1000 kg/m³, g as 10 m/s² and atmospheri...
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solved A Submarine Window At a depth of 1000 m in an ocean, a submarine has a window of area 0.04 m², and its interior is maintained at sea-lev...
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solved A Stone on a String A stone on a string 80 cm long is whirled round a horizontal circle at a steady speed, 14 times in 25 s. What is its ...
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solved A Steel Wire Under Tension A steel wire 0.72 m long has a mass of 5.0 × 10⁻³ kg. If the wire is under a tension of 60 N, what is the speed of tr...
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solved A Steel Wire as Fast as Sound A steel wire has a length of 12.0 m and a mass of 2.10 kg. What should be the tension in the wire so that speed of a ...
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solved A Steel Tape on a Hot Day A steel tape 1m long is correctly calibrated for a temperature of 27.0 °C. The length of a steel rod measured by this...
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solved A Steel Rod Stretched A structural steel rod has a radius of 10 mm and a length of 1.0 m. A 100 × 10³ N force stretches it along its length...
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solved A Steady Push Forward A steady force on a body of 3.0 kg takes it from 2.0 m/s to 3.5 m/s in 25 s, without turning it. How strong is the fo...
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solved A Square Coil in a Field A square coil of side 10 cm consists of 20 turns and carries a current of 12 A. The coil is suspended vertically and ...
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solved A Spring's Mass at Its Hardest Pull A spring having with a spring constant 1200 N/m is mounted on a horizontal table. A mass of 3 kg is attached to the f...
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solved A Spring's Mass at Its Fastest A spring having with a spring constant 1200 N/m is mounted on a horizontal table. A mass of 3 kg is attached to the f...
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solved A Splash Heard from a Tower A stone dropped from the top of a tower of height 300 m splashes into the water of a pond near the base of the tower....
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solved A Spinning Solid Cylinder's Angular Momentum A solid cylinder of mass 20 kg rotates about its axis with angular speed 100 rad/s. The radius of the cylinder is 0.2...
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solved A Spinning Solid Cylinder A solid cylinder of mass 20 kg rotates about its axis with angular speed 100 rad/s. The radius of the cylinder is 0.2...
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solved A Sphere with an Inward Field A conducting sphere of radius 10 cm has an unknown charge. If the electric field 20 cm from the centre of the sphere ...
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solved A Solenoid with an Iron Core A solenoid has a core of a material with relative permeability 400. The windings of the solenoid are insulated from t...
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solved A Solenoid of Five Layers A closely wound solenoid 80 cm long has 5 layers of windings of 400 turns each. The diameter of the solenoid is 1.8 c...
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solved A Soap Film on a Slider A U-shaped wire is dipped in a soap solution, and removed. The thin soap film formed between the wire and the light s...
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solved A Soap Bubble's Excess Pressure What is the excess pressure inside a bubble of soap solution of radius 5.00 mm, given that the surface tension of soa...
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solved A Small Solid's Density A small solid of mass 5.74 g takes up 1.2 cm³. What is its density, in kilograms per cubic metre, to the figures the ...
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solved A Slide on the Screen A slide of 1.75 cm² is thrown onto a screen, where its picture covers 1.55 m². How many times are lengths magnified?
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solved A Skidding Stop A cyclist comes to a skidding stop in 10 m. During this process, the force on the cycle due to the road is 200 N and ...
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solved A Silver Wire Warmed A silver wire has a resistance of 2.1 Ω at 27.5 °C, and a resistance of 2.7 Ω at 100 °C. Determine the temperature co...
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solved A Second at 18 km/h A cyclist rides at a steady 18 km/h. How many metres do they cover in one second?
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solved A Satellite Rocketed Free A satellite orbits the earth at a height of 400 km above the surface. How much energy must be expended to rocket the ...
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solved A Rod Turning in a Ring A metallic rod of 1 m length is rotated with a frequency of 50 rev/s, with one end hinged at the centre and the other...
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solved A Rod Spun against a Ring A 1.0 m long metallic rod is rotated with an angular frequency of 400 rad/s about an axis normal to the rod passing t...
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solved A Rocket Lifts Off A rocket of 20000 kg at lift-off is blasted upward with an acceleration of 5.0 m/s². Taking g as 10 m/s², what is the...
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solved A Rocket Fired Straight Up A rocket is fired vertically with a speed of 5 km/s from the earth's surface. How far from the earth does the rocket ...
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solved A Resistor's Power over a Cycle A 100 Ω resistor is connected to a 220 V, 50 Hz ac supply. What is the net power consumed over a full cycle, in watts?
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solved A Resistor on an AC Supply A 100 Ω resistor is connected to a 220 V, 50 Hz ac supply. What is the rms value of current in the circuit, in amperes?
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solved A Resistor and Capacitor in Series A resistor of 200 Ω and a capacitor of 15.0 μF are connected in series to a 220 V, 50 Hz ac source. What is the curre...
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solved A Raindrop Held Back A drop of mass 1.00 g falls from a height of 1.00 km under gravity, taken as 10 m/s², and an opposing resistive force...
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solved A Radio's Shortest Wavelength A radio can tune in to any station in the 7.5 MHz to 12 MHz band. What is the shortest wavelength of the correspondin...
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solved A Radio's Longest Wavelength A radio can tune in to any station in the 7.5 MHz to 12 MHz band. What is the longest wavelength of the corresponding...
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solved A Pushed Body Gains Kinetic Energy A body of mass 2 kg initially at rest moves under the action of an applied horizontal force of 7 N on a table with co...
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solved A Pure Inductor on AC A pure inductor of 25.0 mH is connected to a source of 220 V. The frequency of the source is 50 Hz. What is the rms c...
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solved A Position Rule A body's position is x = a + bt², where a is 8.5 m and b is 2.5 m/s². How fast is it moving at t = 2.0 s, in m/s?
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solved A Polaroid Between Crossed Polaroids A polaroid sheet is placed between two crossed polaroids, with its pass-axis at 45° to that of the first. What share ...
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solved A Platinum Thermometer The resistance of the platinum wire of a platinum resistance thermometer at the ice point is 5 Ω and at steam point i...
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solved A Pipe Open at Both Ends A pipe, 30.0 cm long, is open at both ends. Taking the speed of sound in air as 330 m/s, which harmonic mode of the p...
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solved A Pipe Closed at One End A pipe 20 cm long is closed at one end. The speed of sound in air is 340 m/s. Which harmonic mode of the pipe is reso...
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solved A Pendulum That Ticks Seconds Taking g as 9.8 m/s², what is the length of a simple pendulum, which ticks seconds, in metres?
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solved A Pendulum Taken to the Moon The acceleration due to gravity on the surface of moon is 1.7 m/s². What is the time period of a simple pendulum on t...
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solved A Pebble Thrown Up A pebble of mass 0.05 kg is thrown vertically upwards. Ignore air resistance, and take g as 10 m/s². What is the magn...
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solved A Parallel Plate Capacitor in Air In a parallel plate capacitor with air between the plates, each plate has an area of 6 × 10⁻³ m² and the distance bet...
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solved A Pan of Hot Food A pan filled with hot food cools from 94 °C to 86 °C in 2 min when the room temperature is at 20 °C. How long will it...
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solved A Nucleus Three Times the Unit Radius The radius of a nucleus is found to be 3.6 fm. Taking R₀ = 1.2 fm, how many nucleons does it hold?
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solved A Nitrogen Nucleus's Binding Energy What is the binding energy of a nitrogen nucleus (A = 14, Z = 7), given its mass 14.00307 u, with mH = 1.007825 u and...
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solved A Nitrogen Molecule's Free Path Take the radius of a nitrogen molecule to be roughly 1.0 Å. Estimate the mean free path of a nitrogen molecule in a c...
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solved A Nitrogen Molecule's Collisions Take the radius of a nitrogen molecule to be roughly 1.0 Å. The molecular mass of N2 is 28.0 g/mol. Estimate the coll...
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solved A Nichrome Element Settling A heating element using nichrome connected to a 230 V supply draws an initial current of 3.2 A which settles after a ...
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solved A Needle Before a Convex Mirror A 4.5 cm needle is placed 12 cm away from a convex mirror of focal length 15 cm. What is the location of the image, i...
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solved A Motor Wheel Speeds Up The angular speed of a motor wheel is increased from 1200 rpm to 3120 rpm in 16 s. Assuming the angular acceleration ...
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solved A Mole of Hydrogen Atoms The unit of length convenient on the atomic scale is known as an angstrom and is denoted by Å: 1 Å = 10⁻¹⁰ m. The siz...
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solved A Microwave's Wavelength In a plane electromagnetic wave, the electric field oscillates sinusoidally at a frequency of 2.0 × 10¹⁰ Hz and ampli...
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solved A Microwave's Magnetic Field In a plane electromagnetic wave, the electric field oscillates sinusoidally at a frequency of 2.0 × 10¹⁰ Hz and ampli...
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solved A Metre-Long Pendulum A pendulum 1 m long swings on the Earth, where g is 9.81 m/s². How long does one swing there and back take, in seconds?
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solved A Metre in Light-Years A light-year is the distance light goes in a year. What is one metre in light-years?
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solved A Mass on a Spring on a Table A spring having with a spring constant 1200 N/m is mounted on a horizontal table. A mass of 3 kg is attached to the f...
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solved A Loop in the Sky An aircraft flies a horizontal loop of radius 1.00 km at a steady 900 km/h. Taking g as 9.8 m/s², how many times g is...
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solved A Locomotive Piston The piston in the cylinder head of a locomotive has a stroke (twice the amplitude) of 1.0 m. If the piston moves with...
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solved A Litre of Water Compressed Taking the bulk modulus of water as 2.2 × 10⁹ N/m², how much should the pressure on a litre of water be changed to co...
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solved A Lift Speeding Up A man of mass 70 kg stands on a weighing scale in a lift which is moving upwards with a uniform acceleration of 5 m/s...
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solved A Lift Speeding Down A man of mass 70 kg stands on a weighing scale in a lift which is moving downwards with a uniform acceleration of 5 m...
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solved A Lift Rising Steadily A man of mass 70 kg stands on a weighing scale in a lift which is moving upwards with a uniform speed of 10 m/s. Taki...
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solved A Lift Falling Freely A man of mass 70 kg stands on a weighing scale in a lift whose mechanism has failed, so that it hurtles down freely u...
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solved A Lead Slab Sheared A square lead slab of side 50 cm and thickness 10 cm is subject to a shearing force of 9.0 × 10⁴ N on its narrow face...
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solved A Kilogram Of Ice In A Kilogram Of Water At Eighty 1 kg of ice at 0 °C is mixed with 1 kg of water at 80 °C. The final temperature of the mixture is (Take specific heat...
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solved A Jump Between Two Levels A difference of 2.3 eV separates two energy levels in an atom. What is the frequency of radiation emitted when the at...
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solved A Joule in Ergs The erg is the unit of work in grams, centimetres and seconds. How many ergs make a joule?
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solved A Jerk Along a String A string of mass 2.50 kg is under a tension of 200 N. The length of the stretched string is 20.0 m. If the transverse...
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solved A Hydraulic Automobile Lift A hydraulic automobile lift is designed to lift cars with a maximum mass of 3000 kg. The area of cross-section of the...
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solved A Human Pyramid In a human pyramid in a circus, the entire weight of the balanced group is supported by the legs of a performer who i...
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solved A Hot Copper Block on Ice A copper block of mass 2.5 kg is heated in a furnace to a temperature of 500 °C and then placed on a large ice block....
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solved A Hole in a Copper Sheet A hole is drilled in a copper sheet. The diameter of the hole is 4.24 cm at 27.0 °C. Coefficient of linear expansion ...
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solved A Helium-Neon Photon's Momentum Monochromatic light of wavelength 632.8 nm is produced by a helium-neon laser. What is the momentum of each photon in...
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solved A Helium-Neon Laser's Photons Monochromatic light of wavelength 632.8 nm is produced by a helium-neon laser. What is the energy of each photon in t...
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solved A Helium Atom on the Sun Estimate the average thermal energy of a helium atom at the temperature on the surface of the Sun (6000 K), in joules?
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solved A Helium Atom in a Star's Core Estimate the average thermal energy of a helium atom at the temperature of 1.0 × 10⁷ K (the typical core temperature ...
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solved A Helium Atom at Room Temperature Estimate the average thermal energy of a helium atom at room temperature (27 °C), in joules?
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solved A Heating Element at 117 Ohms At room temperature (27.0 °C) the resistance of a heating element is 100 Ω. What is the temperature of the element if...
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solved A Harmonic Wave's Speed A transverse harmonic wave on a string is described by y(x, t) = 3.0 sin (36 t + 0.018 x + π/4) where x and y are in ...
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solved A Harmonic Wave's Frequency A transverse harmonic wave on a string is described by y(x, t) = 3.0 sin (36 t + 0.018 x + π/4) where x and y are in ...
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solved A Hair Made Large Under a microscope that makes lengths 100 times larger, a hair looks 3.5 mm wide. How wide is the hair, in metres?
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solved A Glass Slab Under Pressure Taking the bulk modulus of glass as 37 × 10⁹ N/m², what is the fractional change in volume of a glass slab, when subj...
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solved A Girl on a High Heel A 50 kg girl wearing high heel shoes balances on a single heel. The heel is circular with a diameter 1.0 cm. Taking g...
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solved A Force Along a Constrained Path A body constrained to move along the z-axis of a coordinate system is subject to a constant force F given by F = (-1 ...
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solved A Flywheel's Energy A cord of negligible mass is wound round the rim of a flywheel of mass 20 kg and radius 20 cm, at rest on frictionles...
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solved A Flywheel on a Cord A cord of negligible mass is wound round the rim of a flywheel of mass 20 kg and radius 20 cm. A steady pull of 25 N ...
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solved A Floor That Gives Way A wooden block of 2 kg rests on a soft horizontal floor. When an iron cylinder of 25 kg is placed on top of the block...
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solved A 50 MHz Wave's Wavelength Suppose that the electric field amplitude of an electromagnetic wave is E₀ = 120 N/C and that its frequency is ν = 50...
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solved A 50 MHz Wave's Wave Number Suppose that the electric field amplitude of an electromagnetic wave is E₀ = 120 N/C and that its frequency is ν = 50...
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solved A 50 MHz Wave's Magnetic Field Suppose that the electric field amplitude of an electromagnetic wave is E₀ = 120 N/C and that its frequency is ν = 50...
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solved A 50 MHz Wave's Angular Frequency Suppose that the electric field amplitude of an electromagnetic wave is E₀ = 120 N/C and that its frequency is ν = 50...
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solved A Field Dying Away A square loop of side 10 cm and resistance 0.5 Ω is placed vertically in the east-west plane. A uniform magnetic fiel...
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solved A Dust Particle's Wavelength What is the de Broglie wavelength of a dust particle of mass 1.0 × 10⁻⁹ kg drifting with a speed of 2.2 m/s, in m?
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solved A Dipole on the z Axis A system has two charges qA = 2.5 × 10⁻⁷ C and qB = –2.5 × 10⁻⁷ C located at points A: (0, 0, –15 cm) and B: (0, 0, +...
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solved A Dipole at Thirty Degrees An electric dipole with dipole moment 4 × 10⁻⁹ C m is aligned at 30° with the direction of a uniform electric field o...
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solved A Cylinder in a Field An electric field is uniform, of magnitude 200 N/C, pointing away from the plane x = 0 on either side. A right circul...
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solved A Cut-Off of One and a Half Volts The photoelectric cut-off voltage in a certain experiment is 1.5 V. What is the maximum kinetic energy of photoelectr...
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solved A Cut-Off Above the Threshold The threshold frequency for a certain metal is 3.3 × 10¹⁴ Hz. If light of frequency 8.2 × 10¹⁴ Hz is incident on the ...
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solved A Cut Loop Drawn Out Endwise for How Long A rectangular wire loop of sides 8 cm and 2 cm with a small cut is moving out of a region of uniform magnetic field o...
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solved A Cut Loop Drawn Out Endwise A rectangular wire loop of sides 8 cm and 2 cm with a small cut is moving out of a region of uniform magnetic field o...
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solved A Cut Loop Drawn Out Broadside for How Long A rectangular wire loop of sides 8 cm and 2 cm with a small cut is moving out of a region of uniform magnetic field o...
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solved A Cut Loop Drawn Out Broadside A rectangular wire loop of sides 8 cm and 2 cm with a small cut is moving out of a region of uniform magnetic field o...
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solved A Cubic Centimetre How many cubic metres are there in a cube 1 cm on each side?
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solved A Cricket Ball Rises A cricket ball is thrown at 28 m/s, 30° above the horizontal. Taking g as 9.8 m/s², how high does it rise, in metres?
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solved A Cricket Ball Lands A cricket ball is thrown at 28 m/s, 30° above the horizontal. Taking g as 9.8 m/s², how far from the thrower does it ...
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solved A Coulomb One Electron at a Time If 1 × 10⁹ s⁻¹ electrons move out of a body to another body every second, how much time is required to get a total ch...
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solved A Copper Cube Under Pressure Taking the bulk modulus of copper as 140 × 10⁹ N/m², what is the volume contraction of a solid copper cube, 10 cm on ...
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solved A Copper Coin Pulled Apart A given coin has a mass of 3.0 g. For simplicity assume that the coin is entirely made of copper atoms (A = 63, Z = 2...
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solved A Copper Ball in Oil The terminal velocity of a copper ball of radius 2.0 mm falling through a tank of oil at 20 °C is 6.5 cm/s. Density o...
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solved A Converging Beam Through a Convex Lens A beam of light converges at a point P. Now a lens is placed in the path of the convergent beam 12 cm from P. At what...
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solved A Converging Beam Through a Concave Lens A beam of light converges at a point P. Now a lens is placed in the path of the convergent beam 12 cm from P. At what...
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solved A Coil Turned Over A circular coil of radius 10 cm, 500 turns and resistance 2 Ω is placed with its plane perpendicular to the horizonta...
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solved A Coil Turned by a Field A 100 turn closely wound circular coil of radius 10 cm carries a current of 3.2 A. It is free to turn in a uniform ma...
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solved A Coil of a Hundred Turns Consider a tightly wound 100-turn coil of radius 10 cm, carrying a current of 1 A. What is the magnitude of the magne...
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solved A Coil of a Hundred Small Turns A circular coil of wire consisting of 100 turns, each of radius 8.0 cm carries a current of 0.40 A. What is the magni...
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solved A Coil Held Against a Field A circular coil of 30 turns and radius 8.0 cm carrying a current of 6.0 A is suspended vertically in a uniform horizo...
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solved A Clamped String's Wavelength The transverse displacement of a string (clamped at its both ends) is given by y(x, t) = 0.06 sin (2π/3 x) cos (120 π...
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solved A Clamped String's Tension The transverse displacement of a string (clamped at its both ends) is given by y(x, t) = 0.06 sin (2π/3 x) cos (120 π...
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solved A Clamped String's Component Waves The transverse displacement of a string (clamped at its both ends) is given by y(x, t) = 0.06 sin (2π/3 x) cos (120 π...
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solved A Charge in a Gaussian Cube A point charge of 2.0 μC is at the centre of a cubic Gaussian surface 9.0 cm on edge. What is the net electric flux t...
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solved A Charge Above a Square A point charge 10 μC is a distance 5 cm directly above the centre of a square of side 10 cm. What is the magnitude of...
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solved A Chairlift Cable A steel cable with a radius of 1.5 cm supports a chairlift at a ski area. If the maximum stress is not to exceed 1 × ...
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solved A Car Lift In a car lift compressed air exerts a force on a small piston having a radius of 5.0 cm. This pressure is transmitted...
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solved A Car Battery Shorted The storage battery of a car has an emf of 12 V. If the internal resistance of the battery is 0.4 Ω, what is the maxi...
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solved A Capacitor on an AC Supply A 60 μF capacitor is connected to a 110 V, 60 Hz ac supply. What is the rms value of the current in the circuit, in a...
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solved A Capacitor on AC A 15.0 μF capacitor is connected to a 220 V, 50 Hz source. What is the rms current in the circuit, in amperes?
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solved A Capacitor Filled and Squeezed A parallel plate capacitor with air between the plates has a capacitance of 8 pF. What will be the capacitance if the...
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solved A Candle Before a Concave Mirror A small candle, 2.5 cm in size is placed at 27 cm in front of a concave mirror of radius of curvature 36 cm. At what ...
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solved A Calorie Elsewhere A calorie is 4.2 J. In a system whose units of mass, length and time are α kg, β m and γ s, how many of the new units...
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solved A Bullet Through Plywood In a ballistics demonstration a police officer fires a bullet of mass 50.0 g with speed 200 m/s on soft plywood of th...
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solved A Bullet Stopped in Wood A bullet of 0.04 kg moving at 90 m/s enters a heavy wooden block and is stopped after a distance of 60 cm. What is th...
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solved A Bullet's Wavelength What is the de Broglie wavelength of a bullet of mass 0.040 kg travelling at the speed of 1.0 km/s, in m?
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solved A Bullet from a Moving Van A police van doing 30 km/h fires a bullet at 150 m/s, relative to the van, at a car ahead doing 192 km/h the same way...
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solved A Bulb on the Mains A light bulb is rated at 100 W for a 220 V supply. What is the peak voltage of the source, in volts?
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solved A Brass Wire Cooled Between Supports A brass wire 1.8 m long at 27 °C is held taut with little tension between two rigid supports. Co-efficient of linear ...
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solved A Brass Rod Joined to a Steel Rod A brass rod of length 50 cm and diameter 3.0 mm is joined to a steel rod of the same length and diameter. The ends of...
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solved A Box and Two Nuggets A box weighs 2.3 kg. Two gold nuggets of 20.15 g and 20.17 g, together 0.04032 kg, are put into it. What does the box...
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solved A Body in SHM A body oscillates with SHM according to the equation x = (5 m) cos[(2π rad/s) t + π/4]. At t = 1.5 s, what is the spe...
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solved A Body Cools in a Room A body cools from 80 °C to 50 °C in 5 min. The temperature of the surroundings is 20 °C. How long does it take to coo...
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solved A Block on an Oil Film A metal block of area 0.10 m² is connected to a 0.010 kg mass via a string that passes over an ideal pulley. A liquid...
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solved A Block on a Spring A block whose mass is 1 kg is fastened to a spring. The spring has a spring constant of 50 N/m. The block is pulled t...
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solved A Bismuth Nucleus's Binding Energy What is the binding energy of the nucleus of bismuth (A = 209, Z = 83), given its mass 208.980388 u, with mH = 1.0078...
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solved A Beating Heart On an average, a human heart is found to beat 75 times in 1 min. What is its frequency, in hertz?
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solved A Battery on Charge A storage battery of emf 8.0 V and internal resistance 0.5 Ω is being charged by a 120 V dc supply using a series res...
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solved A Bat's Call Reflected off Water A bat emits ultrasonic sound of frequency 1000 kHz in air. Speed of sound in air is 340 m/s. If the sound meets a wat...
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solved A Bat's Call into Water A bat emits ultrasonic sound of frequency 1000 kHz in air. Speed of sound in water is 1486 m/s. If the sound meets a ...
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solved A Bar Magnet Twisted by a Field A short bar magnet placed with its axis at 30° with a uniform external magnetic field of 0.25 T experiences a torque ...
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solved A Bar Magnet Turned across a Field A bar magnet of magnetic moment 1.5 J/T lies aligned with the direction of a uniform magnetic field of 0.22 T. An ext...
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solved A Ball's Wavelength What is the de Broglie wavelength of a ball of mass 0.060 kg moving at a speed of 1.0 m/s, in m?
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solved A Ball off a Roof Rises A ball is thrown straight up at 20 m/s from the top of a building 25 m tall. Taking g as 10 m/s², how high above the ...
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solved A Ball off a Roof Lands A ball is thrown straight up at 20 m/s from the top of a building 25 m tall. Taking g as 10 m/s², how many seconds pa...
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solved A Ball Hit Straight Back A batsman hits back a ball straight in the direction of the bowler without changing its initial speed of 12 m/s. The ...