Blog 2: Projectile Motion

This past weekend, my cousin and I were playing in my grandma's back yard waiting for the UH football game to start. We accidentally hit the ball over the roof and to go to the front of the house to retrieve the ball. Instead of just getting the ball and walking it back to the backyard, my cousin said he could throw the ball over the whole house. I instantly thought of projectile motion and went inside to get my camera to record the motion of the ball. Using kinematic equations, I could have figured out the approximate vertical velocity he had to throw the ball with in order for the ball to get over the roof and land in the backyard. I would've had to known the exact height of the house, how far the ball traveled in the x-direction, and the final velocities of the ball. The roof is gabled so the ball would have to be at it's peak at the highest point of the roof, but my grandma's roof has a metal roof attachment, so the peak of the ball doesn't match the peak of the roof. The first picture is of my cousin throwing the ball from the ball from the front of the house, the second is of the ball approximately at it's peak, and the third is of the ball almost landing in the backyard.

Passing Physics

This weekend as my team and I were warming up for our game, I realized that volleyball has a lot to do with acceleration, velocity, and displacement. The ball always travels at many different speeds and varies in acceleration depending on how hard it is contacted. Also vertically speaking, the displacement of the ball will always be positive if the ground is considered the origin.

Since volleyball is influenced by acceleration, velocity, and displacement, kinematic equations can often be used to determine the speed of the ball and how far it will travel. As a libero, I have to pass a lot of serves and hits. If I can measure how fast the ball is traveling when I pass it, the acceleration of the ball, and how long it takes for the ball to reach its peak, then I can use the kinematic equations to determine the height of the peak of my pass. With these calculations I can see if I need to add more acceleration to get a higher pass or slow the ball down to lower the height of the pass. I can also calculate what speed and acceleration the ball must be moving to pass the ball a certain distance. As I begin to understand physics more and unravel all its concepts, I think I will be able to find more relations to volleyball.