Tennis+Physics+Project

Meg and Gracie Goal: How much energy is lost when a tennis ball bounces off a wall?

Materials Procedure
 * Tennis ball
 * Tennis racket
 * Meter stick
 * Camera
 * Scale
 * 1) Gather materials
 * 2) One person stand 5 meters from the wall and one person recording
 * 3) Hit the ball against the wall while recording
 * 4) Upload video into Logger pro
 * 5) Calculate the initial velocity
 * 6) Calculate the final velocity
 * 7) Determine the initial and final kinetic energy
 * 8) <span style="font-family: Georgia,serif;">Find how much energy was lost

<span style="font-family: Georgia,serif; font-size: 150%;">Lab: <span style="font-family: Georgia,serif;">media type="youtube" key="aRAej1kzIys" height="315" width="420"

<span style="font-family: Georgia,serif; font-size: 150%;">INITIAL VELOCITY: <span style="font-family: Georgia,serif;">

<span style="font-family: Georgia,serif; font-size: 150%;">FINAL VELOCITY:

<span style="font-family: Georgia,serif;">Work: <span style="font-family: Georgia,serif;">Equation: K=1/2mv^2 <span style="font-family: Georgia,serif;">initial: using initial velocity (before the ball hit the wall) which is: 20.73

<span style="font-family: Georgia,serif;">K=1/2(.057)20.73^2 <span style="font-family: Georgia,serif;">K=12.25 J

<span style="font-family: Georgia,serif;">final: using final velocity (after the ball hit the wall) which is : 9.63

<span style="font-family: Georgia,serif;">K=1/2(.057)9.63^2 <span style="font-family: Georgia,serif;">K=2.64 J

<span style="font-family: Georgia,serif;">Energy lost=inital K-final K <span style="font-family: Georgia,serif;">12.25 J-2.64 J=9.61 J

<span style="font-family: Georgia,serif;">Conclusion: <span style="font-family: Georgia,serif;">Our goal was to find how much energy was lost when a tennis ball bounces off a wall. Through our lab, we found the amount of energy lost was 9.61 J. To do this, we knew we had to find the initial amount of kinetic energy and the final amount of kinetic energy. To find this, we recorded ourselves hitting a tennis ball against the wall. We then used Logger Pro to calculate what the initial velocity and final velocity was. The initial velocity of the ball was -20.73 m/s and the final velocity, after it bounced off the wall, was 9.63 m/s. Next we massed the ball on a scale. With this data we were able to calculate the initial and final kinetic energy using the equation: KE= 1/2mv^2. We found that the initial kinetic energy was 12.25 J and the final kinetic energy was 2.64 J. To find how much energy was lost, we subtracted the final velocity from the initial velocity. We found how much energy was lost and we concluded that the reason energy was lost was because the wall did negative work on the ball causing the ball to slow down.