A rubber of volume 2000 cc is alternately subjected to tension and released. The figure shows the stress-strain curve of rubber. Each curve is a quadrant of an ellipse. The amount of energy lost as heat per cycle per unit volume will be

Hysteresis loss corresponding to elasticity per unit volume of a substance is given by the area of hysteresis loop, i.e., stress-strain curve coresponding to one complete loading and deloading.Area of an ellipse = π x semi-majoraxis x semi-minor axisA1 = 14(π×8×4×102) and A2 = 14(π×8×4×102)Also, A3 = 8×4×102Area by hysteresis loop is A = A1+A2-A3A = 2[π4×8×4×102]-[8×4×102]    = work done per cycle    = energy lost per cycle per unit volume