Physics
Lab 3.2 Simple Harmonic Motion
Overview
The purpose of this
laboratory class is to determine the validity of the
pendulum equation and to identify factors that need to be
taken into account when using the pendulum equation.
Experiments
- Measure the period of
a pendulum
- Measure the period of
a pendulum with a relatively high center of mass
Experiment
: The period of a pendulum
Equipment
Stopwatch
String
Metal weight (steel ball
or lead weight)
Strip of wood or metal
tube.
Procedure
- Make a pendulum using
the metal weight and the piece of string.
- Measure the length of
the pendulum. Measure the distance from the
center of the weight to the point at which the
string is tied.
- Allow the pendulum to
swing and use the stopwatch to measure the time
taken for 10 cycles. (Remember that the time for
a cycle is the time taken for the pendulum to
return to the same position from the opposite
direction that it left that position.)
- Compare the time for
one cycle with the period calculated using the
pendulum equation.
- Change the pendulum
so that its center of mass is higher. Fix a strip
of wood or a metal tube to the string.
- Measure the period of
the modified pendulum.
- Compare the value of
the cycle time compared with that for a pendulum
with the same length that has its mass
concentrated mainly at the bottom of the pendulum.
Results
Experiment
|
Length of pendulum
|
Time for 10 Cycles
|
Period
|
Calculated Period
|
1
|
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|
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2
|
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|
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3
|
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Modified Pendulum 1
|
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Modified Pendulum 2
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Calculation
Use the pendulum to
estimate the period of a pendulum with the same length as
the one used for the experiment.
In the pendulum equation,
the length, L, is given in meters and the period, T, is
in seconds. g = 9.81.
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