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The escape velocity for a planet is ve. ...

The escape velocity for a planet 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 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)impliesv=sqrt((3GM)/(R))=sqrt(1.5)v_(e)`
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