Suppose I have a ball colliding with a surface at an oblique angle. I want to know what work will be done on the surface. Now, there is kinetic energy associated with the tangential and normal velocity of the ball. Can I say that the kinetic energy of the ball associated with the normal velocity is the only energy that does work on the surface? That makes sense to me, but I read that kinetic energy is a scalar, so can't be split up. I'm assuming that there is no friction. Any thoughts would be much appreciated.