Lifting with a Lever
A Science Fair Project
By
B
January, 2013
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ABSTRACT
Did you know that you can lift an object that's heavier than you are? Just use a lever! This
science project involved building a tabletop lever and measuring how much effort it takes
to lift an object using it. His hypothesis was that if the length of the effort arm of a lever is
increased, then the amount of effort required to for the lever to lift a load will decrease.
The results proved the hypothesis correct.
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TABLE OF CONTENTS
Title page………………………………………………………………………….1
Abstract…………………………………………………………………………....2
Introduction………………… …………………………………………………….4
Problem …………………………………………………………….……….4
Hypothesis……………………………………………………………..…….4
Independent Variable……………………………………………………….4
Dependent Variable………………………………………………………….4
Constant or Controlled Variables…………………………………………..4
Background Research……………………………………………………….4
List of materials………………………………………………………………….…4
Experimental Procedure…………………………………………………..……….5
Data Table……………………………………………………………………….….7
Graphs………………………………………………………………………………8
Data Analysis and Discussion……………………………………………………...8
Conclusion…………………………………………………………….…………….9
Ideas for Future Research ……………………………………………….………..9
Bibliography………………………………………………………………………...9
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Give It a Lift with the Lever
Problem: How does the length of the effort arm of a lever affect how much load it can lift?
Purpose: To find out how to changing the length of the effort arm of a lever will affect how
much load it can lift’
Hypothesis: If the length of the effort arm of a lever is increased, then the amount of effort
required to for the lever to lift a load will decrease.
Independent Variable: Length of effort arm of the lever
Dependent Variable: Number of Pennies needed to lift the load
Constants:
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

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Same load (bar soap)
Same lever (ruler)
Same fulcrum (pencil)
Same Ziploc bag to hold the pennies
Same type of coins (pennies)
Number of Trials: 3
List of Materials



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Bar soap in still in its box
Ruler
Pencil
Ziploc bag
Masking tape
Table surface
Background Research
A lever is a simple device used for magnifying a force. A lever consists of a beam, and a fulcrum
around which the beam can turn or pivot. It is a type of simple machine. There are three classes
of lever – first class, second class and third class levers. First class levers have the fulcrum
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between the load and effort. Examples of first class levers are scissors, seesaws and pliers.
Second class levers have the load between the effort and the fulcrum. Examples are nail clippers,
staplers and wheel barrows. Third class levers have the effort between the load and the fulcrum.
Examples are tweezers and shovels. Many things we use in life are levers. They make work
easier.
The object being lifted or shifted by the lever is the load. The force applied to lift it is the effort.
The distance between the fulcrum and the effort is known as the effort arm while the distance
between the fulcrum and the load is known as load arm.
Experimental Procedure
1. Make a container out of your plastic bag to hold the pennies in
2. On a small Ziploc bag, put a piece of tape approximately 1 centimeter (cm) from the zipper
part of the top of the bag both on the inside and outside.
3. Cut a slit long enough to allow the ruler to slip through.
4. Put the ruler into the slit from the beginning on of the ruler.
5. Tape the beginning end ruler firmly to the bag and the bar soap at the other end. The ruler
is the lever while the soap is the load.
6. Make the fulcrum of the lever by taping a pencil to the edge of a desk.
7. Place the ruler attached to the bag and bar soap on the fulcrum. The ruler is the lever while
the bar soap is the load. The bar soap should be resting on the desk.
8. The bag will be used to hold the pennies being used as the effort to lift the load at the other
end of the lever.
9. Move the lever so the fulcrum is on 4 cm. This is the length of the effort arm.
10.Keep adding pennies to the bag until the bar soap load is lifted from the desk surface.
Record the number of pennies that lifted the load on the data table.
11.Repeat step 6 for two more trials.
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12.Move the lever on the fulcrum by increasing the length of the effort arm by 2 cm and
repeat steps 6 and 7. Continue until the length of effort arm is 12 cm.
13.Calculate the average number of pennies used for each length of effort arm by adding the
number of pennies from each set of three trials and divide by three and record it on the data
table.
Picture of Lever Experiment in Progress
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Data Table
Levels of
Independent
Variable: Length
of Effort Arm
(cm)
4
6
8
10
DV: Number of Pennies Used to Lift Load
Trial1
292
172
117
78
Trail 2
273
164
110
69
Trail 3
281
170
116
74
Average Number
of Pennies Used
to Lift Load
281
168
114
74
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Give it a lift with a lever
300
281
Number of Pennies
250
200
168
150
Average
114
100
74
50
0
0
1
2
3
4
5
Length of the Effort Arm (Cm)
Data Analysis and Discussion
The data shows that when the effort arm was 4cm, the average number of pennies required to lift
the load was 281. For the length of effort arm 6cm, 8cm, and 10cm, the average number of
pennies that lifted the load were 168, 114, and 74 respectively.
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Conclusion
According to the data, the shortest effort arm needed the greatest number of pennies which was
281 pennies to lift the load. As the length of the effort increased to 6cm, 8cm, and 10cm, the
number of pennies required to lift the load decreased to 168, 114, and 74 respectively. The
hypothesis was if the length of the effort arm of a lever is increased, then the amount of effort
needed to lift will decrease. Therefore the data supports the hypothesis because the greater the
length of the effort arm the fewer the number of pennies to lift the load.
Ideas for Future Research
In the future instead of using centimeter I’m going to use inches. Instead of using a bar of soap I
can use another material as the load to see how they will affect the results.
Bibliography

http://pbskids.org/cyberchase/parentsteachers/show/episodes/604.html

http://pbskids.org/cyberchase/videos/biancas-ups-and-downs

http://www.sciencebuddies.org/science-fairprojects/project_ideas/Phys_p065.shtml#background
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