- #1
Fibo112
- 149
- 3
I am solving a problem where I need to decide if an asteroids velocity is high enough to escape the planets gravitational pull. The way I did it was use conservation of energy and angular momentum to find an expression for the radial velocity and show that it remains positive as r tends to infinity. In the solution all that was done was argue that the sum of potential and kinetic energy is positive. I can see how this would work if v0 is pointing radially outward but I don't see why is holds generally. Does it and if so why.