Percentage uncertainty

Percentage uncertainty basically tells us ‘what percentage of the measurement could we be off by?’

For example, if we have a measurement of 10cm \pm 1cm, that means we could be off by 1cm. To find the percentage uncertainty, we can use the formula:

\text{percentage uncertainty} = \left(\frac{\text{absolute uncertainty}}{\text{measurement}}\right) \times 100\%

For example, to find the percentage uncertainty of our absolute uncertainty example above (5.25cm \pm 0.15cm):

\text{percentage uncertainty} = \left(\frac{0.15cm}{5.25cm}\right) \times 100\% \approx 2.86\%