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The escape velocity for a planet from th...

The escape velocity for a planet from the surface is `v_(e)`. A particle starts from rest at a large distance from the planet, reaches the planet only under gravitational attraction, and passes through a smooth tunned through its centre. Its speed at the centre of the planet will be

A

`sqrt(1.5) v_(e)`

B

`v_(e)/sqrt(2)`

C

`v_(e)`

D

zero

Text Solution

Verified by Experts

The correct Answer is:
A
From mechanical energy conservation, `0+0=1/2 mv^(2) - (3GMm)/(2R) implies v= sqrt((3GM)/R)=sqrt(1.5) v_(e)`.
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