High School Physics

# Gravitation Class 9 MCQ

This post on Gravitation Class 9 MCQ publishes a set of Multiple Choice Questions (with answers) from the class 9 Gravitation chapter.

Gravitation Class 9 MCQ (Multiple Choice Questions with answers)

Q1. The atmosphere consisting of a large number of gases, is held to the earth by:

a) winds

b) clouds

c) earth’s magnetic field

d) gravity

The correct answer is d) gravity

Q2. The force of attraction between two unit point masses separated by a unit distance is called:

a) gravitational potential

b) acceleration due to gravity

c) gravitational field strength

d) universal gravitational constant

The correct answer is d) universal gravitational constant

Q3. The weight of an object at the centre of the earth of radius R is:

a) zero

b) R times the weight at the surface of the earth

c) infinite

d) 1/R2 times the weight at the surface of the earth

The correct answer is a) zero

Q4. Two objects of different masses falling freely near the surface of the moon would:

a) have the same velocities at any instant

b) have different accelerations

c) experience forces of the same magnitude

d) undergo a change in their inertia

The correct answer is a) have the same velocities at any instant

Q5. The value of acceleration due to the gravity of earth:

a) is the same on the equator and poles

b) is the least on poles

c) is the least on the equator

d) increases from the pole to the equator

The correct answer is c) is the least on the equator

Q6. The law of gravitation gives the gravitational force between:

a) the earth and a point mass only

b) the earth and the sun only

c) any two bodies having some mass

d) any two charged bodies only

See also  The formula for acceleration due to gravity at height h - with derivation

The correct answer is c) any two bodies having some mass

Q7. The value of quantity G in the formula for gravitational force:

a) depends on mass of the earth only

b) depends on the radius of the earth only

c) depends on both the mass and radius of the earth

d) depends neither on mass nor on the radius of the earth

The correct answer is d) depends neither on mass nor on the radius of the earth

Q8. Two particles are placed at some distance from each other. If keeping the distance between them unchanged, the mass of each of the two particles is doubled, the value of gravitational force between them will become:

a) ¼ times

b) ½ times

c) 4 times

d) 2 times

The correct answer is c) 4 times

Q9. In the relation F = (G)(M)(m/d2) the quantity G:

a) depends on the value of g at the place of observation

b) is used only when the earth is one of the two masses

c) is the greatest on the surface of the earth

d) is of the same value irrespective of the place of observation

The correct answer is d) is of the same value irrespective of the place of observation

Q10. The gravitational force of attraction between two objects is x. Keeping the masses of the objects unchanged, if the distance between the objects is halved, then the magnitude of the gravitational force between them will become:

a) x/4

b) x/2

c) 2x

d) 4x

See also  How to measure universal gravitational constant | Measurement of G

The correct answer is d) 4x

Q11. An apple of mass 100g falls from a tress because of gravitational attraction between the earth and the apple. If the magnitude of the force exerted by the earth on the apple is F1 and the magnitude of the force exerted by the apple on the earth is F2, then:

a) F1 is very much greater than F2

b) F2 is very much greater than F1

c) F1 is only a little greater than F2

d) F1 and F2 are exactly equal

The correct answer is d) F1 and F2 are exactly equal

Q12. According to one of Kepler’s laws of planetary motion:

a) r2 T3

b) r  T2

c) r3 T2

d) r3 1/T2

The correct answer is c) r3 ∝ T2

Q13. An object is thrown vertically upwards with a velocity u, the greatest height h to which it will rise before falling back is given by:

a) u/g

b) u2/2g

c) u2/g

d) u/2g

The correct answer is b) u2/2g

Q14. The mass of the moon is about 0.012 times that of the earth, and its diameter is about 0.25 times that of the earth. The value of G on the moon will be:

a) less than that on the earth

b) more than that on the earth

c) same as that on the earth

d) about one-sixth of that on the earth

The correct answer is c) same as that on the earth

Q15. The value of g on the surface of the moon:

a) is the same as on the earth

b) is less than that on the earth

c) is more than that on the earth

d) keeps changing day by day