Question

Steel wire of length L at $40^{\circ}C$ is suspended from ceiling and then a mass m is hung from its free end. The wire is cooled down from $40^{\circ}C$ to $30^{\circ}C$ to regain its original length L. The coefficient of linear thermal expansion of the steel is $10^{-5} /^{\circ}C,$, Young’s modulus for steel is $10^11 N/m^2$ and radius of the wire is 1 mm. Assume L diameter of the wire. Then the value of m (in kg) is nearly . . . . . . .

Answer 1

value of m is 777kg per m this is answer