Momentum problem (motion of a system of particles?) Slingshot around moon

demerdar

NASA often uses the gravity of a planet to slingshot a probe on its way to a more distant planet. The interaction of the planet and the spacecraft is a collision in which the objects do not touch. How can the probe have its speed increased in this manner?

This problem confuses me, I want to use the conservation of momentum, but I can't really set it up, if I'm even going in the right direction. I could use some help with this problem. Thanks.

Hootenanny

Welcome to PF!

You are on the right lines with momentum, but you also need to use conservation of kinetic energy.

This page is very useful;
http://www.mathpages.com/home/kmath114.htm

-Hoot