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A body projected vertically from the ear...

A body projected vertically from the earth reaches a height equal to earth.s radius before returning to the earth. The power exerted by the gravitational force is greatest

A

at the highest position of the body

B

at the instant just before the body hits the earth

C

it remains constant all through

D

at the instant just after the body is projected

Text Solution

Verified by Experts

The correct Answer is:
B
Power, `P, vecF. vecv = F v cos theta`
Just before hitting the earth `theta = 0^@` . Hence, the power exerted by the gravitation force is greatest at the instant just before the body hits the earth.
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