Here is what you have to do. You have to throw a ball as hard as you can but it must return back to you even if it does not bounce at anything. Also, you have nothing attached to the ball. There is no one on the other end to catch that ball and throw it back at you.
How will you do it ?
To achieve this, you must throw that ball as hard as you can in the air and gravity will bring it back to you.
