So Imagine a ball moving off a frictionless cliff with a velocity v to the right, at the bottom of the cliff the surface has friction. So after the collision, the x component of the velocity would be reduced, and the angular momentum would be fixed clockwise because the frictional impulse acted to the left. Now clearly the bounce would not be symmetric. But I'm thinking only in the x. The maximum height of the rebound should still be the same, its only the x velocity that was reduced and convered to rotational motion. The y velcocity gets completely reflected back upwards. This is assuming that the ball is rigid enough that it doesn't deform at all during the collision. It just get torqued up. Is this correct?