In volleyball, there are many opportunities to see physics. There is friction, there is newtons first law and many other aspects. First of all, when a hitter goes up to jump to spike the ball, you're pushing down with a force into the ground, while the ground is also pushing the sam force back at you, so you don't fall through the ground. When your hand contacts the ball, the same thing happens, where the ball is pushing back at your hand and your pushing hard at the ball. That ball will stay in motion until it hopefully hits the ground for the kill and the ground stops the ball's motion, or until a player digs the ball and changes it's motion. The ball is also being acted on by gravity, which can change its course from off your hand and to the ground. When your getting ready to hit, you have a lot of potential energy from the time your waiting to start your approach until the actual time you start your approach. When you start your approach you have kinetic energy and are gaining more and more as you accelerate to jump. Unfortunately when you jump you are being acted on by the force of gravity, so you can't stay in the air for that long and also can't jump as high... Can you imagine volleyball without gravity???