Question 440: Gravitation

Question

A body of mass m is placed on earth's surface which is taken from earth surface to a height of h = 3R, then change in gravitational potential energy is

Accepted Answer

Gravitational potential energy on earthÃ¢ÂÂs surface = $$ - {{GMm} \over R}$$, where M and R are the mass and radius of the earth respectively, m is the mass of the body and G is the universal gravitational constant.
Gravitational potential energy at a height h = 3R
$$ =  - {{GMm} \over {R + h}} =  - {{GMm} \over {R + 3R}} =  - {{GMm} \over {4R}}$$
$$ 	herefore $$  Change in potential energy
$$ =  - {{GMm} \over {4R}} - \left( { - {{GMm} \over R}} ight)$$
$$ =  - {{GMm} \over {4R}} + {{GMm} \over R}$$
$$ = {3 \over 4}{{GMm} \over R}$$ $$ = {3 \over 4}mgR$$

Answer

$${{mgR} \over 4}$$

Answer

$${2 \over 3}mgR$$

Answer

$${3 \over 4}mgR$$

Answer

$${{mgR} \over 2}$$

Gravitation

A body of mass m is placed on earth's surface which is taken from earth surface to a height of h = 3R, then change in gravitational potential energy is

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