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

When it orbited the Moon, the Apollo 11 spacecraft’s mass was 7170 kg, its period was 121 min, and its mean distance from the Moon’s center was 1.87167 × 10^{6}m. Assume its orbit was circular and the Moon to be a uniform sphere of mass

7.36 ×10^{22}kg. Its orbital speed was 1619.837645 m/s

What is the minimum energy required for the craft to leave the orbit and escape the Moon’s

gravitational ﬁeld?

Answer in units of J

2. Relevant equations

Don't know of any

maybe U_{G}=-Gm_{1}m_{2}/r

3. The attempt at a solution

U_{G}=(6.67259*10^{−11}*7.36*10^{22}*7170)/1.87167*10^{6}

But I do not think this is right

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# Homework Help: Find minimum energy to escape an orbit

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