Say I have an object which has been shot away from earth at some initial velocity, and I want to find out how long it will take until it's velocity is zero.(adsbygoogle = window.adsbygoogle || []).push({});

If it is moving fast enough, the approximation v = v_{0}+ aΔt doesn't work because the acceleration due to gravity is changing as a function of r. I want to describe v as a function of t, set v equal to zero and solve for t.

This is the attempt I have made to solve this:

[PLAIN]http://img204.imageshack.us/img204/2879/problemw.png [Broken]

Any suggestions?

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# Homework Help: An object travelling away from earth

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