(adsbygoogle = window.adsbygoogle || []).push({}); A tunnel is dug through the centre of the earth.A particle is projected into it with a velocity =(gR)^1/2.Find the time required to to cover the length of the tunnel.The force of attraction is F=GMmx/R^3 where x=distance from centre

Then the time period is T=2*3.14*(R^3/GM)^1/2

And the answer comes out to be Half of the time period

But I am not understanding what to do with the initial velocity.

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# Homework Help: Find the time required to to cover the length of the tunnel.

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