# MCQ Questions For Class 11 Physics Chapter 8 Gravitation

Gravitation Class 11 MCQ with answers has been gathered for students to rehearse. Students can prepare these Gravitation MCQ Class 11 with answers. Each question has four choices with answers. Firstly, Solve all these Questions and check your answer with the right answer. If your answers do not match with the right answer, Don’t worry try again because You need to prepare daily to score higher marks in the Class 11 Physics Exam.

Students can refer to the following MCQ on Gravitation class 11 PDF with Answers provided below based on the latest curriculum and examination pattern issued by CBSE and NCERT. Our teachers have provided here a collection of multiple-choice questions for Chapter 8 Gravitation Class 11 Physics covering all topics in your textbook so that students can assess themselves on all important topics and thoroughly prepare for their exams

## Gravitation Class 11 MCQ Physics Free PDF

We have provided below Class 11 Gravitation MCQ PDF with answers which will help the students to go through the entire syllabus and practice multiple choice questions provided here with solutions. As MCQ Questions for Class 11 Physics pdf download can be really scoring for students, you should go through all problems provided below so that you are able to get more marks in your exams.

Question. A satellite is orbiting around the earth near its surface. If its kinetic energy is doubled, then
(a) it will remain in the same orbit.
(b) it will fall on the earth.
(c) it will revolve with greater speed.
(d) it will escape out of the gravitational field of the earth.

D

Question. Mass of the Earth has been determined through
(a) use of Kepler’s T2/R3 constancy law and Moon’s period
(b) sampling the density of Earth’s crust and using Earth’s radius
(c) Cavendish’s determination of G and using Earth radius and g at its surface
(d) use of periods of satellites at different heights above Earth’s surface and known radius of Earth

C

Question. The escape velocity from the earth’s surface is 11 km/s. The escape velocity from a planet having twice the radius and same mean density as that of earth is
(a) 5.5 km/s
(b) 11 km/s
(c) 22 km/s
(d) None of these

C

Question. Due to rotation of the earth the acceleration due to gravity g is
(a) maximum at the equator and minimum at the poles
(b) minimum at the equator and maximum at the poles
(c) same at both places
(d) None of these

B

Question. The weight of an object in the coal mine, sea level and at the top of the mountain, are respectively W1, W2 and W3 then
(a) W1< W2 > W3
(b) W1= W2 = W3
(c) W1< W2 < W3
(d) W1> W2 > W3

A

Question. Two point masses each equal to 1 kg attract one another with a force of 10–10 N. The distance between the two point masses is (G = 6.6 × 10–11 MKS units)
(a) 8 cm
(b) 0.8 cm
(c) 80 cm
(d) 0.08 cm

C

Question. Consider Earth to be a homogeneous sphere. Scientist A goes deep down in a mine and scientist B goes high up in a balloon. The gravitational field measured by
(a) A goes on decreasing and that by B goes on increasing
(b) B goes on decreasing and that by A goes on increasing
(c) each decreases at the same rate
(d) each decreases at different rates

D

Question. There are _______ gravitational lines of force inside a spherically symmetric shell.
(a) infinitely many
(b) zero
(c) varying number depending upon surface area
(d) varying number depending upon volume

B

Question. There is no atmosphere on the moon because
(a) it is closer to the earth and also it has the inactive inert gases in it.
(b) it is too for from the sun and has very low pressure in its outer surface.
(c) escape velocity of gas molecules is greater than their root mean square velocity.
(d) escape velocity of gas molecules is less than their root mean square velocity.

D

Question. A man waves his arms while walking. This is to
(a) keep constant velocity
(b) ease the tension
(c) increase the velocity
(d) balance the effect of earth’s gravity

D

Question. A missile is launched with a velocity less than escape velocity. The sum of its kinetic and potential energies is
(a) zero
(b) negative
(c) positive
(d) may be positive, negative or zero.

B

Question. What would be the length of a sec. pendulum at a planet (where acc. due to gravity is g/4) if it’s length on earth is l
(a) l/2
(b) 2 l
(c) l/4
(d) 4 l

C

Question. Time period of a simple pendulum inside a satellite orbiting earth is
(a) zero
(b) ¥
(c) T
(d) 2 T

B

Question. The escape velocity of a body depends upon mass as
(a) m0
(b) m1
(c) m2
(d) m3.

A

Question. The radius of a planet is 1/4th of Re and its acc. due to gravity is 2g. What would be the value of escape velocity on the planet, if escape velocity on earth is ve.
(a) e v2
(b) ve 2
(c) 2 ve
(d) e v 2

A

Question. There are two bodies of masses 103 kg and 105 kg separated by a distance of 1 km. At what distance from the smaller body, the intensity of gravitational field will be zero
(a) 1/9 km
(b) 1/10 km
(c) 1/11 km
(d) 10/11 km

C

Question. Taking the gravitational potential at a point infinte distance away as zero, the gravitational potential at a point A is –5 unit. If the gravitational potential at point infinite distance away is taken as + 10 units, the potential at point A is
(a) – 5 unit
(b) + 5 unit
(c) + 10 unit
(d) + 15 unit

B

Question. A planet of mass 3 × 1029 gm moves around a star with a constant speed of 2 × 106 ms–1 in a circle of radii 1.5 × 1014 cm. The gravitational force exerted on the planet by the star is
(a) 6.67 × 1022 dyne
(d) 8 × 1027 Newton
(c) 8 × 1026 N
(d) 6.67 × 1019 dyne

C

Question. The mass of the moon is 1/81 of earth’s mass and its radius 1/4 that of the earth. If the escape velocity from the earth’s surface is 11.2 km/sec, its value from the surface of the moon will be
(a) 0.14 kms–1
(b) 0.5 kms–1
(c) 2.5 kms–1
(d) 5.0 kms–1

C

Question. If the mass of earth is eighty times the mass of a planet and diameter of the planet is one fourth that of earth, then acceleration due to gravity on the planet would be
(a) 7.8 m/s2
(b) 9.8 m/s2
(c) 6.8 m/s2
(d) 2.0 m/s2

D

Question. The ratio of escape velocity at earth (ve) to the escape velocity at a planet (vp) whose radius and mean density are twice as that of earth is :
(a) 1 : 2
(b) 1 : 2 2
(c) 1 : 4
(d) 1 : 2

B

Question. At what height from the surface of earth the gravitational potential and the value of g are –5.4 × 107 J kg–1 and 6.0 ms–2 respectively ? Take the radius of earth as 6400 km :
(a) 2600 km
(b) 1600 km
(c) 1400 km
(d) 2000 km

A

Question. Two astronauts are floating in gravitation free space after having lost contact with their spaceship. The two will
(a) move towards each other.
(b) move away from each other.
(c) become stationary
(d) keep floating at the same distance between them.

A

Question. Two bodies of masses 10 kg and 100 kg are separated by a distance of 2m ( G = 6.67 × 10–11 Nm2 kg–2). The gravitational potential at the mid point on the line joining the two is
(a) 7.3 × 10–7 J/kg
(b) 7.3 × 10–9 J/kg
(c) –7.3 × 10–9 J/kg
(d) 7.3 × 10–6 J/kg

C

Question. The distance of neptune and saturn from the sun is nearly 1013 and 1012 meter respectively. Assuming that they move in circular orbits, their periodic times will be in the ratio
(a) 10
(b) 100
(c) 1010
(d) 1000

C

Question. If the length of a simple pendulum is increased by 2%, then the time period
(a) increases by 2%
(b) decreases by 2%
(c) increases by 1%
(d) decreases by 1%

C

Question. The kinetic energy of a satellite in its orbit around the earth is E. What should be the kinetic energy of the satellite so as to enable it to escape from the gravitational pull of the earth?
(a) 4 E
(b) 2 E
(c) 2 E
(d) E

B

Question. The time period of a satellite in a circular orbit of radius R is T, the period of another satellite in a circular orbit of radius 4 R is
(a) 4 T
(b) T/4
(c) 8 T
(d) T/8

C

Question. If the change in the value of g at the height h above the surface of the earth is the same as at a depth ‘x’ below it, then (both x and h being much smaller than the radius of the earth)
(a) x = h
(b) x = 2 h
(c) x = h/2
(d) x = h2

B

Question. The time period of an earth satellite in circular orbit is independent of
(a) both the mass and radius of the orbit
(c) the mass of the satellite
(d) neither the mass of the satellite nor the radius of its orbit.

D

Question. If value of acceleration due to gravity changes from one place to another, which of the following forces will undergo a change ?
(a) Viscous force
(b) Buoyant force
(c) Magnetic force
(d) All of the above

B

Question. The amount of work done in lifting a mass ‘m’ from the surface of the earth to a height 2R is
(a) 2mgR
(b) 3mgR
(c)2/3 mgR
(d)3/2mgR

D

Question. The radius of the earth is 4 times that of the moon and its mass is 80 times that of the moon. If the acceleration due to gravity on the surface of the earth is 10 m/s2, then on the surface of the moon its value will be
(a) 1 ms–2
(b) 2 ms–2
(c) 3 ms–2
(d) 4 ms–2

B

Question. A satellite of mass ‘m’, moving around the earth in a circular orbit of radius R, has angular momentum L. The areal velocity of satellite is (Me = mass of earth)
(a) L /2m
(b) L /m
(c) 2L /m
(d) 2L /Me

A

Question. Two spherical bodies of mass M and 5M and radii R and 2R respectively are released in free space with initial separation between their centres equal to 12 R. If they attract each other due to gravitational force only, then the distance covered by the smaller body just before collision is
(a) 2.5 R
(b) 4.5 R
(c) 7.5 R
(d) 1.5 R

C

Question. If the radius of the earth were to shrink by one per cent, its mass remaining the same, the acceleration due to gravity In the earth’s surface would
(a) decrease
(b) remain unchanged
(c) increase
(d) None of these

C

Question. A ball is dropped from a satellite revolving around the earth at height of 120 km. The ball will
(a) continue to move with same speed along a straight line tangentially to the satellite at that time
(b) continue to move with same speed along the original orbit of satellite.
(c) fall down to earth gradually
(d) go far away in space

B

Question. Two identical geostationary satellites are moving with equal speeds in the same orbit but their sense of rotation brings them on a collision course. The debris will
(a) fall down
(b) move up
(c) begin to move from east to west in the same orbit
(d) begin to move from west to east in the same orbit

A

Question. Two spherical bodies of mass M and 5 M and radii R and 2 R released in free space with initial separation between their centres equal to 12 R. If they attract each other due to gravitational force only, then the distance covered by the smaller body before collision is
(a) 4.5 R
(b) 7.5 R
(c) 1.5 R
(d) 2.5 R

B

Question. A remote – sensing satellite of earth revolves in a circular orbit at a height of 0.25 × 106 m above the surface of earth.
If earth’s radius is 6.38 × 106 m and g = 9.8 ms–2, then the orbital speed of the satellite is: [2015 RS]
(a) 8.56 km s–1
(b) 9.13 km s–1
(c) 6.67 km s–1
(d) 7.76 km s–1

B

Question. If there were a small gravitational effect, then which of the following forces will undergo a change?
(a) Viscous force
(b) Electrostatic force
(c) Magnetic force
(d) Archimedes’ uplift

D

Question. The density of a newly discovered planet is twice that of earth. The acceleration due to gravity at the surface of the planet is equal to that at the surface of the earth. If the radius of the earth is R, the radius of the planet would be
(a) ½ R
(b) 2 R
(c) 4 R
(d) 1/4 R

A

Question. Imagine a new planet having the same density as that of earth but it is 3 times bigger than the earth in size. If the acceleration due to gravity on the surface of earth is g and that on the surface of the new planet is g’, then
(a) g’ = g/9
(b) g’ = 27g
(c) g’=9g
(d) g’=3g

D

Question. The radii of circular orbits of two satellites A and B of the earth, are 4R and R, respectively. If the speed of satellite A is 3 V, then the speed of satellite B will be
(a) 3 V/4
(b) 6 V
(c) 12 V
(d) 3 V/2

B

Question. A planet moving along an elliptical orbit is closest to the sun at a distance r1 and farthest away at a distance of r2. If v1 and v2 are the linear velocities at these points respectively, then the ratio v1 and v2 is
(a) (r1/r2)2
(b) r2/r1
(c) (r2/r1)2
(d) r1/r2

B

Question. The earth is an approximate sphere. If the interior contained matter which is not of the same density everywhere, then on the surface of the earth, the acceleration due to gravity
(a) will be directed towards the centre but not the same everywhere
(b) will have the same value everywhere but not directed towards the centre
(c) will be same everywhere in magnitude directed towards the centre
(d) cannot be zero at any point

D

Question As observed from the earth, the sun appears to move in an approximate circular orbit. For the motion of another planet like mercury as observed from the earth, this would
(a) be similarly true
(b) not be true because the force between the earth and mercury is not inverse square law
(c) not be true because the major gravitational force on mercury is due to the sun
(d) not be true because mercury is influenced by forces other than gravitational force

C

Question. Different points in the earth are at slightly different distances from the sun and hence experience different forces due to gravitation. For a rigid body, we know that if various forces act at various points in it, the resultant motion is as if a net force acts on the CM (centre of mass) causing translation and a net torque at the CM causing rotation around an axis through the CM. For the earth-sun system (approximating the earth as a uniform density sphere).
(a) the torque is zero
(b) the torque causes the earth to spin
(c) the rigid body result is not applicable since the earth is not even approximately a rigid body
(d) the torque causes the earth to move around the sun