If a rod 10cm in length was measured as 10.5cm, calculate the percentage error

A.

5%

B.

5%

C.

8%

D.

7%

Correct answer is A

Actual measurement = 10cm

approximated value of measurement = 10.5cm

% error = \(\frac{\text{Actual measurement − Approximated}}{\text{Actual measure}}\) × 100

= \(\frac{10 − 10.5}{10}\) × 100

= \(\frac{-0.5}{10}\) × 100

ignore -sign i.e take absolute value

= \(\frac{0.5}{10}\) × 100

= 5 %