A steel rod of length 1m is heated from 25°C to 75°C keeping its length constant. The longitudinal strain developed in the rod is (Given: Coefficient of linear expansion of steel = 12 x 10-6/0C)

Due to the Expansion of the rod due to heating it, the rod develops a strain, trying to resist the change in length. Thus the strain tends to reduce the length of the rod.Strain ⇒ ∆LL = Lα∆θL   ⇒ α∆θStrain ⇒-12 ×10-6×50⇒-6×10-4