# MCQ Questions for Class 11 Physics Chapter 8 Gravitation with Answers

Solving the Gravitation Multiple Choice Questions of Class 11 Physics Chapter 8 MCQ can be of extreme help as you will be aware of all the concepts. These MCQ Questions on Gravitation Class 11 with answers pave for a quick revision of the Chapter thereby helping you to enhance subject knowledge. Have a glance at the MCQ of Chapter 8 Physics Class 11 and cross-check your answers during preparation.

Question 1.
A body is projected vertically from the surface of the earth of radius R with velocity equal to half of the escape velocity. The maximum height reached by the body is
(a) R
(b) R/2
(c) R/3
(d) R/4

Question 2.
When the planet comes nearer the sun moves
(a) fast
(b) slow
(c) constant at every point
(d) none of the above

Question 3.
Keplers second law regarding constancy of arial velocity of a planet is a consequence of the law of conservation of
(a) energy
(b) angular momentum
(c) linear momentum
(d) none of these

Question 4.
The escape velocity for a body projected vertically upwards from the surface of the earth is 11km/s. If the body is projected at an angle of 45° with the vertical, the escape velocity will be
(a) 11 /√2 km/s
(b) 11√2 km/s
(c) 2 km/s
(d) 11 km/s

Question 5.
The radii of the earth and the moon are in the ratio 10 : 1 while acceleration due to gravity on the earths surface and moons surface are in the ratio 6 : 1. The ratio of escape velocities from earths surface to that of moon surface is
(a) 10 : 1
(b) 6 : 1
(c) 1.66 : 1
(d) 7.74 : 1

Question 6.
The escape velocity of a body from the surface of the earth is v. It is given a velocity twice this velocity on the surface of the earth. What will be its velocity at infinity?
(a) v
(b) 2v
(c) √2v
(d) √3v

Question 7.
The period of geostationary artificial satellite is
(a) 24 hours
(b) 6 hours
(c) 12 hours
(d) 48 hours

Question 8.
If the radius of the earth were to shrink by 1% its mass remaining the same, the acceleration due to gravity on the earths surface would
(a) decrease by 2%
(b) remain unchanged
(c) increase by 2%
(d) will increase by 9.8%

Question 9.
The mean radius of the earth is R, its angular speed on its own axis is w and the acceleration due to gravity at earths surface is g. The cube of the radius of the orbit of a geo-stationary satellite will be
(a) r²g / w
(b) R²w² / g
(c) RG w²
(d) R²g / w²

Question 10.
If escape velocity from the earths surface is 11.2 km/sec. then escape velocity from a planet of mass same as that of earth but radius one fourth as that of earth is
(a) 11.2 km/sec
(b) 22.4 km/sec
(c) 5.65 km/sec
(d) 44.8 km/sec

Question 11.
Geo-stationary satellite
(a) revolves about the polar axis
(b) has a time period less than that of the earths satellite
(c) moves faster than a near earth satellite
(d) is stationary in the space

Question 12.
If the radius of the earth were to be rease by 1% its mass remaining the same, the acceleration due to gravity on the surface of the earth will
(a) increase by 1%
(b) decrease by 2%
(c) decrease by 1%
(d) increase by 2%

Question 13.
If the distance between the earth and the sun were half its present value , the number of day in a year would have been
(a) 64.5
(b) 129
(c) 182.5
(d) 730

Question 14.
If the radius of the earth were to shrink by 1% its mass remaining the same, the acceleration due to gravity on the earths surface would
(a) decrease by 2%
(b) remain unchanged
(c) increase by 2%
(d) will increase by 9.8%

Question 15.
If escape velocity from the earths surface is 11.2 km/sec. then escape velocity from a planet of mass same as that of earth but radius one fourth as that of earth is
(a) 11.2 km/sec
(b) 22.4 km/sec
(c) 5.65 km/sec
(d) 44.8 km/sec

Question 16.
The radii of the earth and the moon are in the ratio 10 : 1 while acceleration due to gravity on the earths surface and moons surface are in the ratio 6 : 1. The ratio of escape velocities from earths surface to that of moon surface is
(a) 10 : 1
(b) 6 : 1
(c) 1.66 : 1
(d) 7.74 : 1

Question 17.
Average density of the earth
(a) is a complex function of g
(b) does not de end on g
(c) is inversely proportional to g
(d) is directly proportional to g

Answer: (b) does not de end on g

Question 18.
An infinite number of identical point masses each equal to m are placed at points x = 1, x = 2, x = 4, x = 8m, ……. The total gravitational potential at point at x = 0 is
(a) -Gm
(b) -2Gm
(c) +2Gm
(d) infinite

Question 19.
A body is projected vertically from the surface of the earth of radius R with velocity equal to half of the escape velocity. The maximum height reached by the body is
(a) R
(b) R/2
(c) R/3
(d) R/4

Question 20.
A satellite is revolving around the earth in a circular orbit with a velocity of 7.07 km/s. What minimum increase in its velocity is needed to make it escape gravitational pull of earth?
(a) 4.23 km/s in the direction of its velocity
(b) 11.3 km/s in a direction perpendicular to its velocity
(c) 2.93 km/s in the direction of its velocity
(d) 4.23 km/s in a direction perpendicular to its velocity