NEET Physics Acceleration due to Gravity MCQs Set A

a) increase

b) decrease

c) remain same

d) become half

Answer: increase

Question: The weight of a body at the centre of the earth is

a) zero

b) infinite

c) same as on the surface of earth

d) None of these

Answer:  zero

Question: Weight of body is found less on moon because of

a) smaller value of g

b) smaller value of m

c) smaller value of G

d) smaller value of R

Answer: smaller value of g

Question: Assertion : If earth suddenly stops rotating about its axis, then the value of acceleration due to gravity will become same at all the places.
Reason : The value of acceleration due to gravity depends upon the rotation of the earth.

a) Assertion is correct, reason is incorrect

b) Assertion is incorrect, reason is correct

c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion

d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is correct, reason is incorrect

Question: The acceleration due to gravity on the planet A is 9 times the acceleration due to gravity on planet B. A man jumps to a height of 2m on the surface of A. What is the height of jump by the same person on the planet B?

a) 18 m

b) 6 m

c) 18 m

d) 24 m

Answer: 18 m

Question: Assume that the acceleration due to gravity on the surface of the moon is 0.2 times the acceleration due to gravity on the surface of the earth. If R_e is the maximum range of a projectile on the earth's surface, what is the maximum range on the surface of the moon for the same velocity of projection

a) 5 R_e

b) 0.5 R_e

c) 2 R_e

d) 0.2 R_e

Answer: 5 R_e

Question: The height of the point vertically above the earth's surface, at which acceleration due to gravity becomes 1% of its value at the earth's surface is (Radius of the earth = R)

a) 9 R

b) 8 R

c) 10 R

d) 20 R

Answer: 9 R

Question: The speed of earth’s rotation about its axis is w. Its speed is increases to x times to make the effective acceleration due to gravity equal to zero at the equator. Then x is :

a) 17

b) 34

c) 8.5

d) 1

Answer: 17

More Questions................................

Question: Where will it be profitable to purchase one kilogram sugar?

a) At equator

b) At 40° latitude

c) At poles

d) At 45° latitude

Answer: At equator

Question: Earth is flattened at poles, bulged at the equator. This is due to

a) the centrifugal force is more at the equator than at the poles

b) earth revolves round the sun in an elliptical orbit

c) the angular velocity of spinning about its axis is more at equator

d) the angular velocity of spinning about its axis is less at equator

Answer: the centrifugal force is more at the equator than at the poles

Question: A particle is suspended from a spring and it stretches the spring by 1 cm on the surface of earth. By how much amount the same particle will stretch the same spring at a place 800 km above the surface of earth

a) 0.79 cm

b) 1.38 cm

c) 2.38 cm

d) 1.59 cm

Answer: 0.79 cm

Question: Weight of body is found less on moon because of

a) None of these

b) smaller value of m

c) smaller value of G

d) smaller value of R

Answer: None of these

Question:Assertion : Moon travellers tie heavy weight at their back before landing on the moon.
Reason : The acceleration due to gravity on moon is smaller than that of earth

a) Assertion is correct, reason is correct; reason is a correct explanation for assertion.

b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion

c) Assertion is correct, reason is incorrect

d) Assertion is incorrect, reason is correct

Answer: Assertion is correct, reason is correct; reason is a correct explanation for assertion.

Question: The density of a newly discovered planet is twice that of earth. The acceleration due to gravity at the surface of the planet is equal to that at the surface of the earth. If the radius of the earth is R, the radius of the planet would be

a) 1/2 R

b) 2 R

c) 4 R

d) 1/4 R

Answer: 1/2 R

Question: Imagine a new planet having the same density as that of earth but it is 3 times bigger than the earth in size. If the acceleration due to gravity on the surface of earth is g and that on the surface of the new planet is g’, then

a) g’ = 3g

b) g’= 9g

c) g’ = 27g

d) g’ = g/9

Answer: g’ = 3g

Question: Assertion : Generally, the path of a projectile from the earth is parabolic but it is elliptical for projectiles going to a very large height
Reason : The path of a projectile is independent of the gravitational force of earth.

a) Assertion is correct, reason is incorrect

b) Assertion is incorrect, reason is correct

c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion

d) Assertion is correct, reason is correct; reason is a correct explanation for assertion.

Answer: Assertion is correct, reason is incorrect

Question: Average density of the earth

a) is directly proportional to g

b) is inversely proportional to g

c) does not depend on g

d) is a complex function of g

Answer: is directly proportional to g

Question: If the earth were to rotates faster than its present speed, the weight of an object will

a) decrease at the equator but remain unchanged at the poles

b) remain unchanged at the equator but decrease at the poles

c) remain unchanged at the equator but increase at the poles

d) increase at the equator but remain unchanged at the poles

Answer: decrease at the equator but remain unchanged at the poles

Question: At what height from the ground will the value of g be the same as that in 10 km deep mine below the surface of earth?

a) 5 km

b) 15 km

c) 10 km

d) 20 km

Answer: 5 km

Question: The ratio of radii of earth to another planet is 2/3 and the ratio of their mean densities is 4/5. If an astronaut can jump to a maximum height of 1.5 m on the earth, with the same effort, the maximum height he can jump on the planet is

a) 0.8 m

b) 0.5 m

c) 1.25 m

d) 1 m

Answer: 0.8 m

Question: The value of 'g' at a particular point is 9.8 m/s². Suppose the earth suddenly shrinks 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 now be

a) 9.8 m/sec²

b) 4.9 m/sec²

c) 3.1 m/sec²

d) 19.6 m/sec²

Answer: 9.8 m/sec²

Question: If the density of a small planet is the same as that of earth, while the radius of the planet is 0.2 times that of the earth, the gravitational acceleration on the surface of the planet is

a) 0.2 g

b) 0.4 g

c) 2 g

d) 4 g

Answer: 0.2 g

Question: If the radius of the earth were to shrink by 1%, with its mass remaining the same, the acceleration due to gravity on the earth’s surface would

a) increase by 2%

b) decrease by 2%

c) decrease by 1%

d) increase by 1%

Answer: increase by 2%

Question: If value of acceleration due to gravity is 'g' at a height 50 km above the surface of earth, then at what depth inside the earth will the acceleration due to gravity be same as 'g'?

a) 100 km

b) 50 km

c) 25 km

d) 75 km

Answer: 100 km