1. Name: Bonghee Han
Forces Experiment

3. Science lab Report
Motion and force experiment Bonghee Han
Experiment date‐ 9th/Dec/2010
Group member‐Bonghee, Jaffer, Jungmin
Aim
The purpose of Motion and force experiment is to measure the force of object
and know height is effects to force of dropping or not.
Hypothesis
Dropping the volleyball on the force plate will effect to force. Lower dropping
will affect low, the force will be calculated lower because lower height also affect
to speed of dropping. Higher dropping of the ball will affect higher to the force
plate, than it will be calculated higher. If height is high there is much more time
to be faster. Speed is affect to the force of hitting the force plate.
Variable
Input Variable
Height 25cm, 50cm, 75cm, 100cm
Height of the ball that where the ball will going to drop
Output Variable
Measures the force of dropping ball in newton calculates by the force plate.
Control Variable
#1 Exactly same volleyball
#2 Any force to drop
#3 Same spot to drop the ball on the force plate
Equipment
1. One same volleyball
2. One force plate
3. One meter ruler
4. One stand
5. One clamp
6. Computer
Diagram
S Clamp
T R Ball
A u
N l Computer
D e
r
Force plate

4. Method
1. Set up equipment as shown in diagram
2. Press start button on computer screen
3. Check the force plate is working
4. Measure the height
5. Drop volleyball at measured height
6. Write note of force in trial
7. Repeat experiment four times height of 25cm, 50cm, 75cm, and 100cm
8. Clean up all the equipment used
Data
Table 1‐ Forces of dropping ball
Force (Newton)
Height Trial 1 Trial 2 Trial 3 Trial 4
(cm)
25 101.7 49.6 118.5 131.2
50 161.1 186.7 153.1 189.6
75 173.7 160.4 163.6 183.9
100 241.4 185.2 220.7 241.4
Table 2‐ Average force of dropping ball
Force (Newton)
Height (cm) Average of Trial 1, 2, 3, 4
25 100.25
50 172.63
75 170.4
100 222.18
Graph
Graph 1‐ Average force of dropping ball
Force of dropping ball
250
F
o
r 200
c
e
( 150
N
e
w 100 Force
t
o 50
n
)
0
25cm 50cm 75cm 100cm
Height (cm)

5. Conclusion
By the Data and graph of the experiment tell that if the ball gets higher
results of force. But for trial 2 and 4 there is 50cm dropping more powerful than
75. But except that others has right result. The pattern of the result of the
experiment is higher height higher force of dropping. Low height of dropping the
ball is lower force. The hypothesis of force is correct as it is written down the
height of ball effect to force of the ball. When height of dropping place is at high it
gets more speed than lower height so within gravity and speed. Therefore, the
ball gets power and dropped into the force plate.
Evaluation
Error in Your Effect on Your Improvement to your
Method Data method
The machine that the If the ball does not To improve this error there is
force plate was drop on the same two ways to change. Find out
difficult to drop the
place every times the other machine that can affect
ball in exactly same result is change, same force. Others is redo
place. because edge is dull every times drop at edge.
to measure the force.
Even though the ruler If it is measuring by Use other object to hold the
is held by clamp person it will not be ball and drop to be same
person is measure exactly same because height. For instance one
height by eye and person is moving. person hold object in the
drop the ball by hand. Therefore, height of height and drop for few times.
the place is not same.
The dropping person If the person is Same person can drop in
was changed during changed the power whole experiment. The result
the experiment. they drop could not will be more accurate with
be accurate with other trial.
other trial.