A homogeneous isotropic material has Young's modulus 90 GPa and Poisson ratio 0.25. If its bulk modulus is N GPa, find N.

Question

G1 Physics · Accepted Answer

Use Y = 3K(1−2ν). Therefore, K = Y / [3(1−2ν)]. Substitute: Y = 90 GPa, ν = 0.25. Thus, 1−2ν = 1−0.50 = 0.50. Hence, K = 90 / [3×0.50] = 90/1.5 = 60 GPa. Therefore, N = 60.