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The escape velocity for a planet is v(e)...

The escape velocity for a planet is `v_(e),` A particle starts from rest at a large distance from the planet, reaches the planat only under gravitational attraction and passes through a smooth tunnel 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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