1. The time – period of a satellite of earth is 5 hours. If the separation between the earth and the satellite is increased to 4 times the previous value, the new time – period will become

2. Choose the factor on which the orbital velocity does not depend when the satellite is orbiting close to the earth’s surface

3. 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.

4. A satellite S is move in an elliptical orbit around the earth. The mass of the satellite is very small compared to the mass of the earth .

5. If the density of Earth is doubled keeping its radius constant then acceleration due to gravity will become (the present value is 9,8 ms^-2)

6. If the density of Earth is doubled keeping its radius constant then acceleration due to gravity will become (the present value is 9,8 ms^-2)

7. 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

8. The acceleration due to gravity’ increases by 0.5% when we go from equator to poles. What will be the time period of the pendulum at the equator which beats seconds at the poles?

9. What happens to the weight of the body if the weight becomes 1/16 at a certain. Also, consider the radius of the earth to be R.

10. 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

11. Two satellites of mass m, and 10m, are put in the same orbit around the sun. If T₁ and T₂ be their time periods, then T1/T2=

12. If the distance between the earth and the sun were half its present value, the number of day in a year would have been

13. The escape velocity of projection from the earth is approximately (R = 6400 km)

14. What percentage of the potential energy is gained by the body in rising through a height equal to the radius of the Earth assuming that the gravitational potential energy of a body infinite distance away from Earth is zero.

15. If the radius of the earth were to be raise by 1% its mass remaining the same, the acceleration due to gravity on the surface of the earth will

16. A bail of weight W is thrown vertically upwards. The apparent w eight during the upward motion will be

17. Who among the following first gave the experimental velocity of G?

18. What happens to the gravitational potential at the centre of the uniform spherical shell which shrinks gradually?

19.  The atmosphere around the earth is held by

20. There is no atmosphere on the moon because