Pendulum coursework

PLAN:

String

Ruler
B A Weight

Stand

Desk


Timer

The time period for a pendulum is the time taken for the pendulum to swing from one point to another (i.e. from A to B and back again)
I need to record this time period, but it is too short, so I will time 10 periods and then divide the final time by 10 to give me the time of one pendulum time period.
When doing this experiment I will need to take in account the three variables; Displacement, the mass of the pendulum, and the length of the string that the pendulum is attached to. I have decided to vary the variables in the following way:

Displacement (0)
80
20

Length Of String (cm)
80
20

Mass Of Pendulum (g)
200
500

I have chosen to use this figures because they are wide apart and I will find out how many figures I will need to use in my final experiment.
In my preliminary experiments I am only going to vary one variable at a time, when I use mass as a constant I will set it as 100g, this is becaus...