Ball Bounce
Name ____________________________________
Observations: Almost any material, when in the shape of a sphere, will bounce when dropped onto a firm surface. Some
materials seem to bounce higher than others do. Many different questions can be asked about the height of the bounce of
different materials. Some questions that might be asked: How high will a wooden sphere bounce? Will a steel ball
bounce? Would it make any difference in the height a ball would bounce if one ball was solid and another was hollow?
Today let us look at another question.
Question: How high will a rubber-ball bounce when dropped from various heights?
What is the IV? _____________________________ What is the DV? ____________________________________
TQ: How will ___________________________________ affect ________________________________________?
A good experiment should have only one Independent Variable: only one part of the experiment is changed.
Hypothesis: Make a prediction as to what you think will happen to the height of a bounce if a rubber-ball is dropped from
different heights. In a way you need to make an educated guess as to how high each bounce will be.
Dropped from 10 inches or 50 cm, I predict the bounce will = _______________.
Dropped from 20 inches or 100 cm, the bounce will = _________________.
The materials needed - at least two people, a yard (meter) stick, a rubber-ball, and a hard surface. If a rubber-ball cannot
be found try a golf ball or some other object that has the shape of a sphere.
Procedure/Data Recording: 1. The first step in this experiment is that one person should drop the ball, and another
person should observe how high the ball bounces. 2. Record your observations in the chart below. To be consistent
always place the bottom of the ball at the level from which it is going to be dropped from. 3. Then observe the height at
which the bottom of the ball bounces. Be sure to drop the ball from the same place three times, and record the height of
the bounce each time. 4. Add up each of these sets of numbers and divide by three to get the average height of the
bounce. False data could show up if the ball was dropped only once from each level. This is because a person could
make errors in the way the ball is released or the way the person observed the height. A set of three drops should reduce
the effect of errors.
Dropped from: Height of Bounces in inches (do 3 times) Average Height of Bounces
Ball 1
Dropped From:
5 inches (10 cm)
10 inches (25 cm
15 inches (38 cm)
20 inches (50cm)
25 inches (63 cm)
30 inches (75 cm)
35 inches (88 cm)
40 inches (100cm)
45 inches (113 cm)
50 inches (125 cm)
Height 1 (in CM)
Height 2 (in CM)
Height 3 (in CM)
Average (in CM)
Graph the average bounce height for the different drops.
Conclusion: Answer the Testable Question AND state whether your Hypothesis was correct. (How did your
hypothesis compare to the pattern of different bounces?)
If you used a rubber-ball to do this experiment, do you realize a mathematical equation could be used to represent the
graph that resulted from the experimental data? It would be very close to x = 3/4y, where x = the height of the bounce and
y = the distance the ball fell. In other words, the bounce would be about 75% of the distance the ball fell. This would be
true for each level the ball was dropped from in your experiment.
Dropped from: Height of Bounces in inches (do 3 times) Average Height of Bounces
Ball
Dropped From:
5 inches (10 cm)
10 inches (25 cm
15 inches (38 cm)
20 inches (50cm)
25 inches (63 cm)
30 inches (75 cm)
35 inches (88 cm)
40 inches (100cm)
45 inches (113 cm)
50 inches (125 cm)
Height 1 (in CM)
Height 2 (in CM)
Height 3 (in CM)
Average (in CM)
Dropped from: Height of Bounces in inches (do 3 times) Average Height of Bounces
Ball
Dropped From:
5 inches (10 cm)
10 inches (25 cm
15 inches (38 cm)
20 inches (50cm)
25 inches (63 cm)
30 inches (75 cm)
35 inches (88 cm)
40 inches (100cm)
45 inches (113 cm)
50 inches (125 cm)
Height 1 (in CM)
Height 2 (in CM)
Height 3 (in CM)
Average (in CM)
Dropped from: Height of Bounces in inches (do 3 times) Average Height of Bounces
Ball
Dropped From:
5 inches (10 cm)
10 inches (25 cm
15 inches (38 cm)
20 inches (50cm)
25 inches (63 cm)
30 inches (75 cm)
35 inches (88 cm)
40 inches (100cm)
45 inches (113 cm)
50 inches (125 cm)
Height 1 (in CM)
Height 2 (in CM)
Height 3 (in CM)
Average (in CM)