(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The escape speed from the surface of the Earth is 11.2 km/s. What would be the escape speed be from another planet of the same density (mass per unit volume) as Earth but with a radius 5 times that of Earth's?

2. Relevant equations

I know I have to use v=sqrt2GM/R

3. The attempt at a solution

I wasn't really sure how to go about this problem, but I did v_{1}/v_{2}= 11.2/v_{2}= sqrt5

So I solved for v_{2}by doing 11.2/(sqrt5) and I got 5.00879227.

I have tried 5, 5.0, and 5.009 as answer submissions and got them all incorrect. I am not even sure if I am setting the problem up right, so any guidance or hints would be much appreciated. Thanks!!

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# Homework Help: Escape speed from the Earth

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