Page 1 : Physics, Physics || MCQ’s, MCQ’s || Gravitation|, Gravitation| Std., Std. 11th, 11th || MHT-CET/JEE/NEET, MHT-CET/JEE/NEET, WORKSHEET (CLASS WORK), 1), 2), , 3), , UNIT -I, The ratio of S.I. unit to C.G.S. unit of ‘G’ is, a) 100, b) 1000, c) 1/100 d) 1/1000, The gravitational constant G is experimentally, determined by, 9), a) simple pendulum, b) Compound pendulum, c) Cavendish method, d) torsional pendulum, Gravitational attraction on Earth surface on the, stone of mass M is Fs. If the force on hydrogen, balloon of mass M located at the same space is 10), FB, then, a) FS > FB, b) FS < FB, c) FS, , 4), , 5), , 6), , 7), , 8), , FB, , d) FS, , FB, , If Earth comes to standstill the weight of bodies, lying on its equator shall, a) increase, b) decrease, c) remains same, d) fly, A man standing in a lift which is falling freely, undergravity releases ball from his hand the ball, seen by him, a) moves down, b) moves up, 11), c) moves up and down d) remains stationary, A satellite revolves around the Earth in an, elliptical path its speed is, a) same at all points on the orbit, 12), b) greatest when it is farthest from Earth, c) greatest when it is closest to the Earth, d) nothing can be predicted, A satellite is revolving around Earth in a circular, orbit whose radius is R work done by, gravitational force in one revolution is, a) zero, b) 2 mgR2, c) mgR2 d) mgR, The value of acceleration due to gravity (g) at, poles is maximum and at equator is minimum, this is due to the reason, , 11th (Sci.), , a) Earth is covered with atmosphere, b) that Earth is bulged at equator & flattened, at poles, c) Earth’s spin about its own axis, d) both ‘b’ and ‘c’, The value of ‘g’ is maximum, a) on the surface of Earth, b) at the centre of the Earth, c) in an aeroplane at a height of 1 km, d) in a mine at a depth of 1 km below the Earth, surface, The graph between acceleration due to gravity, and height from surface of Earth is given by, , 1, , If r is distance between any point in the interior, of the Earth and the Earth centre, the value of, ‘g’ varies as, a) r, b)1/r, c) r2, d) 1/r2, , A) There are points outside the Earth where, value of g is equal to its value at equator, B) There are points out side the Earth where, the value of ‘g’ is equal to its value at the poles., a) both ‘A’ and ‘B’ are correct, b) ‘A’ is correct ‘B’ is wrong, c) ‘B’ is correct ‘A’ is wrong, d) both ‘A’ and ‘B’ are wrong, MCQ’s -Gravitation

Page 2 : 13), , 14), , 15), , 16), , 17), , A wooden ball and iron ball of same radius are, released from the same height h in vacuum. We, find that, a) wooden ball reaches the ground first, b) iron ball reaches the ground first, c) both reach the ground at same time, d) can’t say, The value of g on Moon is 1/6th of that on the, Earth. A balloon filled with H2 will, a) fall with an acceleration g/6 on the Moon, b) rise with an acceleration g/6 on the Moon, c) fall with acceleration g only, d) rise with acceleration ‘g’, If the Earth stops rotating about its axis. The, acceleration due to gravity will remain, unchanged at, a) latitude 450, b) latitude 60°, c) poles, d) equator, A man is carrying a stone equal to double his, weight (w) on his head. If he jumps from terrace, of a building during his fall the weight, experienced by the man will be a) w, b) 3w, c) 0, d), Acceleration due to gravity ‘g’ and the mean, density of the Earth are related by the relation,, where G is the gravitational constant and Re is, the radius of the Earth, , a), , 18), , ρ, , b), , 4, π Re, 3, , 2gR, , b), , gR, , c) 2gR, , 22), , 3, G, , 23), , 24), , 26), , 27), , G, 3, , b), , c), , 3G, , d), , 3G, , The period of satellite close to the surface of, the Earth is,, a), , d) gR, , 2, , If the earth is at one fourth of its present, distance from the Sun, the duration of the year, will be, a) half the present year, b) one eighth the present year, c) one fourth the present year, d) one sixth the present year, An artificial satellite has to be set to revolve, around the planet in a circular orbit close to its, surface if density of the planet is and R is its, radius then the period of revolution is, a), , ρ, , The velocity of satellite revolving close to Earth, is v. In order to make a satellite on Earth free, from gravitational field required increase in, velocity in percentage is, a) 10%, b) 41.4% c) 60% d) 100%, , 11th (Sci.), , 21), , 25), , g, G, ρ, g 4, 3, c) G 3 R e, d) 4π 3, R, 3 e, A small body of mass m falls to the Earth from, infinite distance away what will be its velocity, on reaching the Earth, radius of the earth = R,, acceleration due to gravity on the surface of, the earth is g, a), , 19), , g 4π 3, Re, G 3, , g, G, , 20), , 2, , R, g, , b), , 2, , g, R, , c) 2, , gR, , d), , 2g, , R, , What must be period of revolution of Earth so, that bodies on equator feels weightless, a) 1032 sec, b) 84.58 min, c)129 sec, d) 8 hour, A satellite is orbiting revolution the earth at a, mean radius 16 times that of the geostationary, orbit, the period of the satellite is, a) 4 day b) 8day c)16 day d) 64 day, An Earth satellite is moved from a circular orbit, to another greater height of circular orbit., Which (one or more) of the following, quantities will increase for the satellite, a) potential energy, b) kinetic energy, c) acceleration, d) all of these, The gravitational-potential energy of a body, at a distance r from the centre of the Earth is, U. What will be its weight at that location?, a) U/r2, b) Ur2, c) U/r, d) Ur, The radius of Earth is R and acceleration due, to gravity at its surface is ‘g’. If a body of mass, m is sent to a height of R/4 from Earth’s surface,, the potential energy increases by, mgR, mgR, mgR, mgR, b), c), d), 3, 4, 5, 6, The escape velocity of a particle of mass m, varies as proportional to, a) m2, b) m, c) m°, d) m-1, a), , 28), , MCQ’s -Gravitation

Page 3 : 29), , 30), , 36), , The orbital speed of Jupiter is a) greater than the orbital speed of the Earth b) less than the orbital speed of the Earth, c) equal to the orbital speed of the Earth, d) zero, The variation of acceleration due to gravity as, one moves away from Earth’s centre is given by, , 37), , 38), , 31), , 32), , 33), , 34), , 35), , A man inside an artificial satellite feels, weightlessness because the force of attraction, due to Earth is, a) zero at the place, b) is balanced by the force of attraction due to Moon, c) equal to the centripetal force, d) not effective due to particular position of the, satellite, The distance of the geostationary satellite from, the centre of the earth (Radius R) is nearest to, a) 5R, b) 6R, c)7R, d)8R, If the horzontal velocity given to a satellite is, greater than critical velocity but less than the, escape velocity, the satellite will :, a) Revolve in elliptical orbit., b) Revolve in circular orbit., c) Fall on the earth along parabolic path., d) Be lost in space., If g is acceleration due to gravity on the surface, of the earth, its value at a point at a distance, 3R form the surface of the earth will be ......., (R = radius of the earth), a) g / 3, b) 3 g, c) g / 9, d) g / 16., The dimensions of the gravitational constant G are, a) [M-1 L3 T-2 ], b) [ M3 L1 T-2 ], c) [ M1 L3 T-2 ], d) [ M-3 L3 T-3 ], , 11th (Sci.), , 39), , 40), , 41), , 42), , 3, , An object is dropped from a space craft orbiting, in circular orbit around the earth. The object will, a) Fall down on the earth., b) Move in circular orbit of same radius., c) Escape the gravitational field of the earth., d) Travel in a straight line along its direction of, projection., Potential energy of a body of mass m in a, gravitational field of a planet is zero. The body, must be at :, a) Centre of the planet., b) The surface of the planet., c) Infinite distance., d) A distance equal to the radius of the planet., If the radius of the earth were to shrink by 10%, its mass remaining constant, the acceleration due, to gravity on its surface would:, a) Ramain same., b) Decrease by 20 %, c) Increase by 20 %, d) Increase by 10 %, The binding energy of a body does not depend, upon, a) Mass of the planet., b) Its distance form the centre of the planet., c) Mass the body., d) Shape of the body., The binding energy of a satellite of mass m in a, circular orbit at height h form the surface of the, planet of mass M and radius R is :, a) mGm / ( R + h)., b) mGM / 2 (R + h)., 2, c) mGM / (R + h), d) -mGM / 2 ( R + h)2, The observer on the earth will see the same body, in the above question travel :, a) Vertically upward to a greater height and then, fall vertically downward., b) Vertically upward to a greater height and, revoleve around the earth at that height., c) Along parabollic path to a greater height and, fall back to the satellite along parabollic path., d) Along parabollic path in infinity., In order to find time, the astraunut orbiting, around the earth should use :, a) A pendulum clock., b) A spring clock., c) Either a pendulum or a spring clock., d) Neither a pendulum nor a spring clock., MCQ’s -Gravitation

Page 4 : 43), , 44), , 45), , 46), , 47), , 48), , 49), , 50), , 51), , 52), , There is no atmosphere on the moon because, a) Gravitational force of the earth is much, larger and attracts all the molecules there., b) Centrifugal force acting on the molecules is, greater that the escape velocity., c) The themal velocity of the molecules is, greater than the escape velocity., d) There is no gravitational force on the moon., The period of a satellite in circular orbit of, radius R is T. The period of another satellite in, a circular orbit of radius in a circular orbit of, radius 4 R is,, a) 4 / T, b) T / 4, c) 8 T, d) T / 8, Distance between two masses doubled the, gravitational attraction between them, a) becomes twice, b) becomes thrice, c) reduced to half, d) reduced to quarter, A planet revolves in a elliptical orbit around, the sun remains constant is, a) velocity, b) kinetic energy, c) momentum, d) angular momentum, The lengh of seconds pendulum on earth is about, a) 80 cm., b) 100 cm., c) 120 cm., d) 160 cm., The tidal waves in the sea are due to, a) gravitational effect of the moon on the earth, b) gravitational effect of sun on the earth., c) gravitational effect of venus on the earth., d) atmospheric effect of earth itself., An air bubble and a steel ball in water, a) attract each other., b) repel each other., c) neither attract nor repel each other., d) may attract or repel depending upon sizes., A missile when projected into the air follows, a) a straight line path b) an elliptical path, c) an hyperbolic path d) a parablic path., The average magnitude gravitational field on, earth is, a) zero, b) 10 c) 100 d) more than 100, Time period of geostationary satellite is, a) 48 hours, b) 36 hours, c) 24 hours, d) 12 hours, , 11th (Sci.), , 53), , 54), , 55), , 56), , 57), , 58), , 59), , 60), , 4, , A geostationary satellite, a) is stationary satellite, b) time period less than that of earth's satellite, c) moves faster than earth's, d) revolves about the polar axis., The weight of a body at the centre of the earth is, a) zero, b) infinite, c) same as on the surface of earth, d) none of the above., The apparent weight of a man in a lift is less, than the real weight when the lift is going., a) up with an acceleration, b) down with an acceleration, c) up with uniform speed., d) down with uniform speed., If a body describes a circular motion under, inverse square field, the time taken to complete, one revolution T is related to theradius of the, circular orbit r as :, a) T, r, b) T r2, c) T2, r3, d) T, r4, To an astronaut in a spaceship the sky appears, pitch dark. This is due to, a)The absence of atmosphere in his neighbourhood, b) Liht form the sky is absorbed by the medium, surrounding him., c) the fact that at height sky radiations are only, in the infrared and the ultraviolet., d) The fact that the human eye becomes blind, for the blue colour., The height of a geostationary satellite form the, centre of the earth is above., a) 36000 km, b) 42400 km, c) 40400 km, d) 44400 km, Which is the weakest force ?, a) Gravitational, b) Electromagnetic, c) Nuclear, d) Electrostatic, When a body is immersed in a liquid, it loses, a) Mass, b) Weight, c) Both mass and weight, d) Neither mass nor weight, MCQ’s -Gravitation

Page 5 : 61), , 62), , 63), , 64), , 65), , 66), , 67), , Gravitational force is weaker than electrostatic, and nuclear forces, because a) value of G is very small, b) value of G is independent of medium, c) value of G is very large, d) none of these., The spin direction of rotation of earth about, its own axis is a) from west to east, b) from east to west, c) from north to south d) from south to north, The ratio of acceleration due to gravity at, height h above earth's surface to the, acceleration due to gravity at earths surface is, a) R2e / (Re + h)2, b) Re + h / Re, 2, 2, c) (Re+h) / Re, d) Re + h / Re, If we go below the suface of earth, then the, value of g will, a) decrease, b) increase, c) remain same, d) be zero., The heavenly bodies revolving round the sun, are known as, a) stars, b) planets, c) satellites, d) black holes., If the horizontal velocity Vh imparted to, satellite is less than the critical velocity (Vc), then the satellite will a) follow elliptical path, b) follow a parabolic path and fall back to earth, c) escape into space, d) follow circular path, The expression for critical velocity VC of a, satellite revolving close to earth's surface is, a) Vc =, , 68), , geRe, , b) Vc =, , 69), , 70), , 71), , 72), , 73), , 74), , 75), , Gme / Re, , c) both a and b, d) Vc = GMe / Re, The relay satellite transmits the TV programme, continuously from one part of the world to, another because its a) Period is greater than the period of rotation, of the earth., b) Period is less than the period of the earth, about its axis., c) Period has no relation with the period of the, earth about its axis., d) Period is equal to the period of rotation of, the earth about its axis., , 11th (Sci.), , 76), , 5, , A missile is launched with a velocity less than, the escape velocity. The sum of its kinetic and, potential energy is a) Positive, b) Negative, c) Zero, d) May be positive or negative depending upon, its initial velocity., An earth satellite is moved from one stable, circular orbit to a farther stable circular orbit,, which one of the following quantities increase, a) Gravitational force, b) Gravitational P.E., c) Linear orbital speed, d) Centripetal acceleration, If the earth stops rotating, the value of 'g' at the, equator willa) Increase, b) Remain same, c) Decrease, d) None of the above., Which is the most intense planet of the solar, system, a) Saturn, b) Mars, c) Venus, d) Mercury., A particular star has mass twice that of sun. This, star will end up eventually as a a) Black hole, b) White dwarf, c) Black dwarf, d) Red dwarf., The earth rotates round the sun in an elliptical, orbit. Its speed, a) Is greatest when it is closest to the sun, b) Goes on decreasing continuously., c) Greatest when it is farthest from the sun., d) Remains the same at all points on the orbit., Consider a satellite going round the earth in a, circular orbit. Which of the following statement, is wrong a) It is moving with constant speed, b) It is freely falling body., c) Its angular momentum remains constant, d) It is acted upon by a force directed away, from the centre of the earth which counter, balances the gravitational pull., Which of the following is true for gravitational, potential, a) Its SI unit in Joule/kg., b) it is scalar quantity., MCQ’s -Gravitation

Page 6 : c) its proper sign is negative, , UNIT - II, , d) all of the above., 77), , 78), , 1), , a) shape of earth, , b) rotation of earth, , There are two bodies of masses 100 kg & 10000, kg seperated by a distance 1m. At what distance, from the smaller body, the intensity of, gravitational field will be zero ?, , c) constant value of G, , d) both (a) and (b)., , a) 1/11 m, , b) 1/10 m, , a) 1/9 m, , d) 10/11 m, , The variation of value of 'g' on surface of earth, is due to, , The escape velocity of a body from everywhere, is, , 2), , a) depending upon the mass of body, b) independent of mass of body angle and, direction of projection., , a)Will increase by 1 % b) Will decrease by 1 %, c)Will decrease by 2 % d) Will increase by 2 %, , c) independent of mass of planet., 3), , d) independent of mass and distance of body, from centre of planet., 79), , 80), , The magnitude of the total energy of a body in, orbit is equal to the magnitude of, a) potential energy, , b) kinetic energy, , c) 1/2 (K.E.), , d) P.E. + K.E./2., , 4), , b) the earth has population, c) the velocity of escape is less than the mean, velocity of its molecules., d) the velocity of escape is more than the mean, speed of molecules., , 82), , 84), , c), , d), , ., , If the earth be one half of its present distance, from the sun, the number of days in one year, will be, a) 129, , 83), , 5), , The distances of two planets from the sun are, 1013 and 1012 m respectively. The ratio of time, periods of these two planets is :, b), , b) 182, , c) 365, , b) 1 / 400 radian / sec., , c) 1 / 800 radian / sec. d) 1 / 1600 radian / sec., , The earth retains its atmosphere because :, , a) 100, , The radius of the earth is 6400 km and g = 10, m/sec2. In order that a body of 5 kg weighs zero, at the equator, the angular speed of the earth is, a) 1 / 80 radian / sec., , a) the earth is a sphere, , 81), , If the radius of earth were to decrease by 1 %,, its mass remaining the same, the acceleration, due to gravity on the surface of the earth -, , 6), , d) 730., , If the angular speed of the earth is doubled,, the value of acceleration due to gravity (g) at, the north pole, , The value of 'g' at a particular point is 9.8 m/, s 2 . Suppose the earth suddenly shrinks, uniformly to half its present size without losing, any mass. The value of 'g' at the same point, (assuming that the distance of the point from, the centre of earth does not shrink) will now be, a) 4.9 m / sec2., , b) 3.1 m / sec2., , c) 9.8 m / sec2., , d) 19.6 m / sec2., , The density and acceleration due to gravity of, the moon are (3/5)th and (1/6)th those of the, earth respectively. If the radius of the earth is, 5.4 x 106 m, how much is it for the moon a) 1.5 x 106 m, , b) 3.6 x 106 m, , c) 4.5 x 106 m, , d) 5.4 x 106 m, , Orbital velocity of earth's satellite near the, surface is 7 Km/sec. When the radius of the, orbit is 4 times than that of earth's radius then, orbital velocity in that orbit is a) 3.5 Km/sec., , b) 7 Km/sec., , c) 14 Km/sec., , d) 72 Km/sec., , a) Velocity, , b) Angular momentum, , The radius of a planet is (1/4)th of earth's radius, and its acceleration due to gravity is double to, earth's acceleration due to gravity. The value, of escape velocity of the planet as compared, to its value at the earth is -, , c) Potential energy, , d) Acceleration, , a), , a) Doubles, , b) Becomes half, , c) Remains same, , d) Becomes zero., , 7), , Which is constant for a satellite in orbit, , 11th (Sci.), , 6, , 2 ve . b), , 2 ve. c), , 2 ve ., , d) 2 ve., , MCQ’s -Gravitation

Page 7 : 8), , 9), , a), 10), , 11), , 13), , 14), , 15), , 1), , 2 / 5 year, , 3), , b) 2 / 5 year, , c) (2 / 5)2 year., d) (2 / 5)3/2 year., A body weights 100N on the surface of the, earth. Its weight an a height equal to half the, radius of the earth is, a) 44.44 N b) 50 N c) 22.22 N d) 55.55 N., Two satellites x and y are moving in circular orbit, of raddi r and 2r respectively around the same, planet. The ratio of their critical velocity is, a), , 12), , 2), , The value of acceleration due to gravity on the, earth's surface is g. If the diameter of the earth, becomes double of its present value and its mass, remains unchanged, the value of acceleration due, to gravity on the earth's surface would becomes, a) g/2, b) g/4, c) 2g, d) 4g., The mean radius of the earth's orbit around the, Sun is 1.5 x 1011m and that of the orbit of, mercury is 6 x 1010 m. The mercury will revolve, around the sun in nearly., , 2 :1, , b) 2 : 1, , c) 1 : 2, , d), , 4), , a) 2 2 s, 5), , 3 :1, , The escape velocity from the earth is about 11.2, km/s. The escape velocity from a planet having, radius twice and the same mean density as the, earth will be, a) 22.4 km/s, b) 11.1 km/s., c) 55.5 km/s., d) 15.5 km/s., Two satellites are orbiting around the earth in, circular orbits of the same radius. One of them, 100 times greater in mass than the other. The, ratio of period of revolution is, a) 100 : 1 b) 10 : 1 c) 1 : 10 d) 1 : 1., 'g' on certain planet is 5 times that on the earth., The length of second's pendulum there would, be n times that on the earth, n=, a) 2.5, b) 5.0, c) 0.5, d) 25., The acceleration due to gravity about the earth's, surface would be half of its value on the surface, of the earth at an altitude of (R = 4000 miles), a) 1200 miles, b) 8000 miles, c) 1600 miles, d) 4000 miles, UNIT - III, The weight of a body at earth's surface is W. At, a depth half way to the centre of the earth it, will be (assuming uniform density in earth ), a) W, b) W / 2, c) W/4, d) W / 8., , 11th (Sci.), , A body weighs 700 gm on the surface of the, earth. How much will it weigh on the surface of, a planet whose mass is 1/7 and radius half of the, earth?, a) 200 gm-wt, b) 400 gm-wt, c) 50 gm-wt, d) 300 gm-wt, If g be the acceleration due to gravity on the, earth's surface, the gain in the potential energy, of an object of mass m raised from the surface, of the earth to a height equal to the radius R of, the earth is -., a) (1/2) mgR., b) 2 mgR., c) mgR., d) (1/4) mgR., The mass and diameter of a planet are twice, those of the earth. A second's pendulum is taken, to this planet, its period on the planet will be, , c), , 7), , 8), , 9), , 7, , c) 2 s, , d) 1/2 s, , R and r are the raddi of the earth and moon, respectively. e and m are the densities of earth, and moon respectively. The ratio of acceleration, due to gravity on the surfaces of earth and moon, is, a), , 6), , b) 1 / 2 2 s, , R, r, , m, , r, R, , e, , b), , e, , m, , d), , r, R, R, r, , m, e, , e, m, , A man of weight W enters a lift. When the lift, moves upwards with an acceleration a. the, apparent weight of the man is, a) W (1 -a / g), b) W (1 - g / a), c) W (1 + a / g), d) W (1 + g / a), The orbital velocity near the surface of earth is, approximately, a) 7.9 km/s, b) 11.2 km/s, 6, c) 2.189 x 10 m/s, d) 4.4 km/s., A mass M is broken in two parts. m and (M m). Relation between m and M so that the force, of gravitation between the two parts is, maximum is a) M + m2., b) m = M/2, c) mM = 2, d) None of these., The distance of the centres of moon and earth, is D. The mass of earth is 81 times the mass of, the moon. At what distance from the centre of, the earth, the gravitational force will be zero., a) D/2, b) 2D/3, c) 4D/3, d)9D/10., MCQ’s -Gravitation

Page 8 : 10), , If a satellite revolving in an orbit of radius r, has time period of 8 hour, a time period of, another satellite revolving around the same, planet in an orbit of radius 2r will be, a) 64 hour., c) 16, , 11), , 12), , 13), , 14), , 15), , 16), , 2 hour.., , b) 32, , 2 hour.., , d) 48 hour., , If the radii of two planets are in the ratio 4 : 1, and their densities are in the ratio 1 : 2, the, acceleration due to gravity on their surfaces, will be in the ratio, a) 1 : 2, b) 2 : 1, c) 1 : 4, d) 4 : 1, At what angular speed should the earth rotate,, so that a man standing on equator will feel, complete weightlessness ? (Re = 6.4 x 106m), a) 123.7 x 10-3rad / sec., b) 1.237 x 10-3 rad / sec., c) 12.37 x 10-3rad / sec., d) 0.1237 x 10-3 rad / sec., Escape velocity of a body on the surface of, the earth is :, a)5 km/s. b)7 km/s. c)9 km/s. d) 11 km/s., R is radius of a planet and is its density. The, escape velocity on its surface is :, a) R, , 8 G /3, , b) R2, , 8 G /3, , c) R, , 4 G /3, , d) R2, , 4 G /3, , The value of acceleration due to gravity on, the surface of earth be denoted by g. If the, radius of earth is 6400 Kms. Then the value, of acceleration due to gravity 3200 Km. Above, the surface of earth is, a) 2/3 g, b) 4/9 g, c) g/2, d) 2 g, What would be the duration of year if the, distance between sun and earth gets doulbed?, (given : T1 = 365 days = 1 year, period of, earth about sun), a) 10.32 days, b) 103.2 days, c) 1032 days, d) 1.032 days, ********, , 11th (Sci.), , 8, , MCQ’s -Gravitation