Gravity and the Simple Pendulum
Hypothesis:
Since the period depends only on the length and on gravity, it is possible by measuring the period and the length of the pendulum to calculate ‘g’ (g is acceleration due to gravity). The length of the string needs to be measured very accurately to the centre of gravity of the mass to get the accurate value of ‘g’.
Method:
Equipment used:
String (7m)
Mass (2x50g)
Clamp
Retort Stand
Stop Watch
Measuring Tape
Protractor
- The pendulum was hung from the top floor of the school down to the ground floor a few centimeters off the ground.
- The length of the string was measured with the measuring tape.
- We displaced the pendulum 5º from its equilibrium position.
- The pendulum was given a push.
- The stopwatch was started.
- When the pendulum had completed 10 back-and-forth swings the stopwatch was stopped.
- The time taken for the pendulum to complete 10 back-and-forth swings was then recorded in a result’s table.
- The steps 3-7 were repeated 3 times.
- The 3 results were recorded and then added up and divided by 3 to find out the average time taken for the pendulum to make 10 back-and-forth swings.