(Assuming all circular orbits)
Say there is a star with mass M and a planet orbiting that star with a mass m.
The star M then suddenly loses half of its mass. (So now it is M/2)
What is the new radius of orbit of the planet around the star? Warning: Velocity will not be the same!
I'm not sure how to tackle this problem. I know for sure it has to do with angular momentum
L=Iω or r x p angular momentum
The Attempt at a Solution
conservation of momentum for the planet
from Iωi = Iωf, I got m ri vi = m rf vf , but that doesn't really help