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

A projectile is fired straight away from the moon from a base on the far side of the moon, away from the earth. What is the projectile's escape speed from the earth-moon system?

2. Relevant equations

Escape velocity = sqrt[2GM/R]

3. The attempt at a solution

What I'm wondering is, do I just have to use this formula the moon or do I have to take the gravitational potential energy of the earth and the projectile into account also?

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# Homework Help: Moon earth system escape velocity

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