How to calculate the percentage error of a measurement?

To calculate the percentage error of a measurement, you need to follow a simple formula.

Firstly, determine the absolute error of the measurement. This is the difference between the measured value and the true value. For example, if you measure the length of a rod as 10cm, but the true length is 9.8cm, the absolute error is 0.2cm.

Next, calculate the relative error by dividing the absolute error by the true value. In the above example, the relative error would be 0.2/9.8 = 0.0204.

Finally, multiply the relative error by 100 to get the percentage error. In the above example, the percentage error would be 2.04%.

It is important to note that the percentage error is a measure of the accuracy of the measurement, not the precision. Precision refers to the level of detail in the measurement, while accuracy refers to how close the measured value is to the true value.

In physics, it is important to minimise the percentage error in measurements to ensure reliable and accurate results. This can be achieved through careful calibration of equipment, repeated measurements, and using appropriate units and significant figures.