Question

Choose the incorrect statements from the following:

• A. It is possible to shield a body from the gravitational field of another body by using a thick shielding material between them
• B. The escape velocity of a body is independent of the mass of the body and the angle of projection
• C. The acceleration due to gravity increases due to the rotational of the earth.
• D. The gravitational force exerted by the earth on a body is greater than that exerted by the body on the earth

Answer 1

Answer: (A), (C), (D)

It is possible to shield a body from the gravitational field of another body by using a thick shielding material between them
The acceleration due to gravity increases due to the rotational of the earth.
The gravitational force exerted by the earth on a body is greater than that exerted by the body on the earth

statement (a) is incorrect; there is no method by which a body can be shield from the gravitational field of another body.
statement (b) is correct. The escape velocity of a body is independent of the mass of the body and the angle of projection
statement (c) is incorrect. As the earth rotates about its axis,a boy on the surface of the earth also rotates with it. since the body is in a rotating frame, it experiences an outward centrifugal force against the inward force of gravity. As a result, the acceleration due to gravity decreases due to rotation.
statement (d) is incorrect, the forces are equal in magnitude but opposite in direction.
Hence choices (a), (c) and (d) are wrong.