Question

A steel tape gives correct reading at
20°C. It measures the length of a
wooden log at 30°C as 10m. The
error in the measurement is
(a = 12 x 10-6/°C)
(A) 1.2 mm
(B) 2.4 mm
(C) 0.6 mm
(D) 3.6 mm​

Answer 1

Explanation:

Since at 20 degree temperature steel tape measures correct measurement of wood

Now at 0 degree length is 25 cm therefore, when temperature is shifted the scale reading 25 cm will increase and therefore the length which is 25 cm at 0 degree will be less than 25 cm at 20 degree.

option (B)