A brass rod of cross-sectional area 1 and length 0.2 m is compressed lengthwise by a weight of 5 kg. If Young's modulus of elasticity of brass is and , then increase in the energy of the rod will be
U=12×(stress)2Y×volume=12×F2×A×LA2×Y=12×F2LAY=12×(50)2×0.21×10−4×1×1011=2.5×10−5J