10 QA on law of gravitation | Learn Physics

 10 Question-Answer on law of gravitation

1.       If the universal gravitation constant was time dependent, then which of the following quantities would be conserved:

(a)    Potential energy

(b)   Kinetic energy

(c)    Linear momentum

(d)   Angular momentum

Ans: ( d)

2.       If the distance between the sun and the earth is increased by three times  then attraction between two will:

(a)    Remains constant

(b)   Decrease by 63%

(c)    Decrease by 83%

(d)   Decrease by 89%

Ans: (d)

3.       The acceleration due to gravity on the planate is 1.96 ms². If it is safe to jump from a height of 3 m on the earth, the corresponding height on the planate will be:

(a)    3 m

(b)   6 m

(c)    9 m

(d)   15 m

Ans : ( d)

4.       The tidal wave in the sea are primarily due to gravitational effect of:

(a)    Earth on the sea

(b)   Sun on the earth

(c)    Earth on the moon

(d)   Moon on the earth

Ans: (d)

5.       The ratio between masses of two planets is 2 : 3 and the ratio between their radii is 3 : 2. The ratio between acceleration due to gravity on these two planets is:

(a)    4:9

(b)   8:27

(c)    9:4

(d)   27:8

Ans: (b)

6.       If g_e and g_p denote the acceleration due to gravity on the surface on the earth and another planet whose mass and radius are twice that of earth, then the ratio g_p/ g_e  is:

(a)    ½

(b)   √2

(c)    1

(d)   2

Ans: ( a)

7.       Two planets have the same density but different radii. The acceleration due to gravity would be:

(a)    Same on both the planets

(b)   Greater on the smaller planet

(c)    Greater on the larger planet

(d)   Depends of the distance of planet from the sun

Ans: (c)

8.       If the radius of the earth were to shrink by two percent, its mass  remaining the same, the acceleration due to gravity on the earth’s surface would:

(a)    Decrease by 2%

(b)   Increase by 2%

(c)    Increase by 4%

(d)   Decrease by 4%

Ans: ( c)

9.       If earth suddenly shrinks by one third of its present radius, the acceleration due to gravity will be:

(a)    2g/3

(b)   3g/2

(c)    4g/9

(d)   9g/4

Ans: (d)

10- Two point masses at a given distance exert a gravitational interaction force on earth other equal to F. If one mass is doubled, the other is halved, and the distance between them is doubled, the resulting interaction force is:

(a)    F/4

(b)   F/2

(c)    2F

(d)   4F

Ans: (a)