A steel measuring tape is calibrated correctly at 20 °C. On a hot afternoon when the temperature is 35 °C, the tape is used to measure the length of a corridor and shows a reading of 500 cm. The coefficient of linear expansion of steel is 1.1×10−5K−1.
a. (i) Determine the true length of the corridor at 20 °C.
b. (ii) Calculate the percentage error introduced by using the tape at 35 °C instead of at its calibration temperature.