Name: ______________________________________
Period: ______
Date: ________________
Coefficient of Restitution Lab
Objective: To measure the coefficient of restitution for two different balls.
Materials:
Meter stick
bouncy ball
Golf ball
Procedure:
1. You will begin by dropping the bouncy ball from a height of 100 cm (one meter). You will record the
height it reaches when it comes back up after the first bounce, then measure the height again after the
second bounce, and then again after the third and fourth bounce. Record these heights in the table. You
may need to perform multiple trials in order to get a good reading.
2. Repeat the process with the golf ball.
3. Measure the mass of each ball, and use this value to calculate the potential energies at each height.
Data:
Bouncy Ball Mass = _____________ g
Bounces
Height (cm)
0
100
Golf Ball Mass = _____________ g
GPE (dyne)
Height (cm)
GPE (dyne)
100
1
2
3
4
Analysis:
1. In order to calculate the coefficient of restitution (CR) for each ball, you need to use the following
equation:
𝐶! =
𝑏𝑜𝑢𝑛𝑐𝑒 ℎ𝑒𝑖𝑔ℎ𝑡
𝑑𝑟𝑜𝑝 ℎ𝑒𝑖𝑔ℎ𝑡
a) What is the coefficient of restitution for the bouncy ball? (Use the first bounce height)
b) What is the coefficient of restitution for the golf ball? (Use the first bounce height)
2. Is there a big difference between the two values? Why do you think this is?
3. What do you think happened to the energy that the balls lost?
Toy Poppers Lab
Objective:
Next, you will determine how much elastic energy the pop-up toy has when turned inside out. Since you
can’t measure the elastic energy of the popper very easily, we will calculate its gravitational potential
energy when it pops up.
Data:
Record all measurements for at least 3 trials in the table below (you will need to figure out what materials
and measurements are needed).
Analysis:
1. How much GPE does the toy have at its highest point when it pops up?
Show your work.
2. Complete the first three energy transformations for the toy below. The first one is given for you.
Elastic Potential Energy ! _____________________________ ! _____________________________
3. Does this energy stay with the toy forever? If not, where does the energy go?