BITSAT 2017 Paper

A steel wire of length ‘L’ at 40°C is suspended from the ceiling and then a mass ‘m’ is hung from its free end. The wire is cooled down from 40°C to 30°C to regain its original length ‘L’. The coefficient of linear thermal expansion of the steel is 10–

5

°

C, Young’s modulus of steel is 1011N/m2 and radius of the wire is 1 mm. Assume that L >>diameter of the wire. Then the value of ‘m’ in kg is nearly