# Reliable ––- Errors

## Errors

• human error problems with our own human fallibility

## Expt.A

Use your stop clock to find the time for one and only one complete swing. This is called the PERIOD of the pendulum

Record attempt 1 in the table as shown below

Repeat this measurement three more times

Put all results in a neat table as shown, indicating how precise your readings are

Record each measurement to an appropriate number of significant figures

Expt Attempt Time / s Sig. Figs.
A 1 +/-
2 +/-
3 +/-
4 +/-
B 1
C 1

## Results

Expt. B Find the time once and only once for 5 complete swings. Calculate and record the Period.

Expt. C Find the time once and only once for 20 swings. Calculate and record the Period.

Expt. D Find the time once and only once for 50 swings. Calculate and record the Period.

Questions …. To be answered in full sentences:

• What sort of error occurs in each of the above expts, and why ?

• If you had to choose a number of swings to find a reliable value for the Period, is there an optimum number of swings to use, and why ?

Extension if time:

Refer to your How science works” sheets … how could you reduce each of the errors:

• ## anomalous values?

Apparatus: Stopclock. Simple pendulum.