A metal tape is calibrated at 25 ° C . On a cold day when the temperature is - 15 ° C , the percentage error in the measurement of length is (Coefficient of linear expansion of metal = 1 × 10 - 5 C - 1 ∘ )

Step-by-step solution

Length of the steel tape can be written as, L = L 0 1 + α ( T - 25 ° ) Now, percentage error in measurement can be written as, ∆ L L × 100 % = α ( T - 25 ° ) × 100 = 1 × 10 - 5 - 15 ° - 25 ° × 100 = 0 . 04 %