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

Correct Answer: Option A

Explanation

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 %

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