title: Unity 2D Physics Material 2D issue bounciness
body: <p>I'm a beginner and I'm trying to make a simple game: Pong.<br />
  I've used the physics material with 0 friction and 1 bounciness for the ball, so I don't have to make every collision by code. <br />
  The problem is the following: if the ball has a low degree angle and hit the ground (or the ceiling), the ball will start move only horizontally and stop to bounce. Why dodes this happen?</p>
  <p>Here is a little gif with the problem:</p>
  <p><a href="https://i.stack.imgur.com/CYxMY.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/CYxMY.gif" alt="Problem of the ball not bouncing correctly" /></a></p>
  <p>Thanks! Ask me anything if needed</p>