Justin Geeslin

Eng Physics I - M 1:00

Experiment Nine – Pendulum Periods


  1. Introduction

In this experiment, the periods of a pendulum will be studied. A period consists on one complete cycle of movement. There are 3 factors that can change a pendulum’s period. The three variables include the amplitude of the swing, the length of the pendulum, and the mass of the pendulum bob. This is controlled experiment will demonstrate the effects of all three.

  1. Procedure

The first five trials will involve a constant mass of 200g and a constant length of about 1m. The variable in this case will be the amplitude. Amplitude will be measured in degrees. The data should be as follows.


Amplitude (°)

Avg Period (s)

5

2.058

10

2.067

20

2.082

25

2.097

30

2.118


The next section will involve a constant mass of 200g and amplitude of 20 degrees but, a varying length. Begin the first of six trials at a length of 100 cm. The following trials will decrement by 10cm (90cm, 80cm, etc.) Data as follows:


Length (cm)

Avg Period (s)

100

2.087

90

2.001

80

1.884

70

1.788

60

1.649

50

1.498







The final three trials will involve a varying mass with constant amplitude and height. Data as follows:


Mass (g)

Avg Period (s)

100

1.484

200

1.496

300

1.545



Questions

  1. Logger Pro reports every other time because it is looking for the time for a period not just a rise and fall of the pendulum.

  2. Yes, the period does apparently depend on length.