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A body of mass m is situated at a distan...

A body of mass m is situated at a distance `4R_(e)` above the earth's surface, where `R_(e)` is the radius of earth. How much minimum energy be given to the body so that it may escape

A

`mgR_(e)`

B

`2mgR_(e)`

C

`(mgR_(e))/(5)`

D

`(mgR_(e))/(16)`

Text Solution

Verified by Experts

The correct Answer is:
C
to escape from the earth total energy of the body should be zero KE+PE=0
`(1)/(2)mv^(2)-(GMm)/(5R)=0impliesKEmin=(mgR_(e))/(5)`
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