NCERT MCQ CLASS-9 CHAPTER-10 | GRAVITATION | EDUGROWN

NCERT ON GRAVITATION

Question 1 : The mass of an object is

• a) The amount of matter contained in the object, independent of where that object is found
• b) The force of gravity on that object located at a particular point in space
• c) Dependent on whether the object is on the Earth or elsewhere.
• d) Divided by the Earth acceleration due to gravity to equal force.

Answer: a. The amount of matter contained in the object, independent of where that object is found

Question 2: Which of the following was NOT a contribution of Newtons to science?

• a) The first good experimental measure of G, the gravitational constant of proportionality
• b) The law of universal gravitation
• c) F = ma
• d) Explanations of optical phenomena

Answer: a. The first good experimental measure of G, the gravitational constant of proportionality

Question 3: If the distance between objects increases, then the gravitational force between the objects will:

• a) Decrease
• b) None of these
• c) Remain same
• d) Increase

Answer:  a. Decrease

Question 4: The relation between the weight of an object on the moon (W_M) and on the earth (W_E)

• a) W_M =1/6 (W_e)
• b) W_e = 1/6W_M
• c) W_M= W_e
• d) W_M =6 W_E

Answer: a. W_M =1/6 (W_e)

Question 5: The weight of an object is:

• a) Equal on both earth and moon
• b) Greater on earth and lesser on moon
• c) Lesser on earth and greater on moon
• d) None of these

Answer: b. Greater on earth and lesser on moon

Question 6: The upward force exerted by the liquid displaced by the body when it is placed inside the liquid is called

• a) Centripetal force
• b) Gravitational force
• c)Buoyant force
• d) Force of gravitation

Answer :c. Buoyant force

Question 7: SI Unit of pressure is

• a) Pascal
• b) Newton
• c) m/s
• d) Dyne

Answer: a. Pascal

Question 8: The force acting on an object perpendicular to the surface is called

• a) Thrust
• b) Pressure
• c) Weight
• d) Weight

Answer: a. Thrust

Question 9: The expression for finding the gravitational force of attraction between any two bodies is

• a) F = Gm₁/r
• b) F= G m₁m₂/r
• c) F= G m₁m₂/r³
• d) F= Gm₁ m₂/r²

Answer: d.  F= Gm₁ m₂/r²

Question 10: The force which keeps the body to move in circular motion when accelerated is

• a) Centripetal force
• b) Magnetic force
• c) Force of gravitation
• d) Electrostatic force

Answer: a. Centripetal force

Question 11: The time of ascent when measured from the point of projection of a body projected upwards , the

• a) Time of ascent=Time of descent
• b) Time of ascent > Time of descent
• c) Time of ascent < Time of descent
• d) All of the above

Answer: a. Time of ascent=Time of descent

Question 12: Weight of an object on the surface of the moon is

• a)1/3 that on the surface of the earth
• b) 1/5 that on the surface of the earth
• c) 1/6 that on the surface of the earth
• d) 1/2 that on the surface of the earth

Answer: c. 1/6 that on the surface of the earth

Question 13: The value of acceleration due to gravity at the poles

• a) Is more than at the equator
• b) Same as at the equator
• c) Is less than at the equator
• d) Zero

Answer: a. Is more than at the equator

Question 14: The value of acceleration due to gravity at the highest point of the motion of the body when a body is projected upwards

• a) 9.8 m/s² upwards
• b) 0 m/s²
• c) 6 m/s²
• d)9.8 m/s² downwards

Answer: d. 9.8 m/s² downwards

Question 15: The value of acceleration due to gravity of the surface of the earth is

• a) 9.8 m/s²
• b) 6 m/s²
• c) 8 m/s²
• d) 4.9 m/s²

Answer: a. 9.8 m/s²