Required Practical 7: Simple Harmonic Motion: Simple Pendulum

Question 1

Describe a method to investigate the simple harmonic motion of a simple pendulum

Answer 1

1) set up apparatus
2) adjust the suspension so the length of string with pendulum bob attached is 1.5m
3) pull the pendulum to the side with a small amplitude and release
5) start the stopwatch when it passes the fiducial marker
6) stop stopwatch after 10 oscillations and record this value
7) divide this value by 10 to get the time period
8) decrease length by 0.1m and repeat. Reduce length by 0.1m each time until L is 0.5m
9) repeat experiment twice more to find and record a mean value of t for each L
10) plot a graph of T^2 against L and draw a line of best fit
11) the gradient is 4pi^2 / g

Question 2

How can you improve this experiment

Answer 2

• use a small pendulum bob so its easier to measure the length to its centre of mass
• the angle of the max amplitude shouldn’t be more than 15 degrees
• a motion tracker and data logger van be used to eliminate random error