300+ TOP MCQs on Gravitation and Answers

2. The value of ‘g’ at a particular point is 9.8 m/sec2 suppose the earth suddenly shrink 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 the earth does not shrink) will become

(a) 9.8 m/sec2

(b) 4.9 m/sec2

(c) 19.6 m/sec2

(d) 2.45 m/sec2

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

(a) 7 km/sec

(b) 112 km/sec

(c) 12.2 km/sec

(d) 1.1 km/sec

4. If the earth is 1/4th of its present distance from the sun, the duration of the year would be

(a) 1/4 of the present year

(b) 1/6 of the present year

(c) 1/8 of the present year

(d) 1/16 of the present year

5. The period of a satellite in a circular orbit of radius R is T. The period of another satellite in circular orbit of radius 4R is

(a) T/4

(b) 8T

(c) 2T

(d) T/8

6. When the planet comes nearer the sun moves

(a) fast

(b) slow

(c) constant at every point

(d) none of the above

7. Kepler’s 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

8. The period of geostationary artificial satellite is

(a) 24 hours

(b) 6 hours

(c) 12 hours

(d) 48 hours

9. A thief stole a box with valuable article of weight ‘W’ and jumped down a wall of height h. Before he reach the ground he experienced a load of

(a) zero

(b) W / 2

(c) W

(d) 2 W