Physics:Gravitation:1

1. A satellite is revolving around the sun in a circular orbit with uniform velocity v. If the gravitational force suddenly disappears, the velocity of the satellite will be
(a) infinity
(b) 2v
(c) v
(d) zero

2. If the radius of the earth were to shrink by one percent, its mass remaining the same, the acceleration due to gravity on the earth’s surface would
(a) decrease
(b) increase
(c) remains unchanged
(d) none of these

3. A planet has twice the radius but the mean density is 1/4th as compared to earth. What is the ratio of the escape velocity from the earth to that from the planet?
(a) 3 : 1
(b) 1 : 2
(c) 1 : 1
(d) 2 : 1

4. The masses of two planets are in the ratio 1 : 2. Their radii are in the ratio 1 : 2. The acceleration due to gravity on the planets are in the ratio.
(a) 5 : 3
(b) 2 : 1
(c) 3 : 5
(d) 1 : 2

5. What would be the duration of the year if the distance between the earth and the sun gets doubled?
(a) 129 days
(b) 365 days
(c) 730 days
(d) 1032 days  

Answers:

1. c
2. b
3. c
4. d
5. d