First calculate strain energy change U Second, Calculate The work done W. Then, calculate G (W-U)/ change in displacement 7) Consider a single, elastic fiber

 

First calculate strain energy change ΔU

Second, Calculate  The work done ΔW.

Then, calculate G (ΔW-ΔU)/ change in displacement

7) Consider a single, elastic fiber of diameter d, embedded in a rigid half-space. Suppose that the fiber is debonded from the substrate to a depth of a, as shown below. If a tensile force P is applied to the fiber, calculate the strain energy release rate for growth of the debond in terms of P, d, and E (modulus of elasticity of the fiber). You can assume the fiber protrudes from the surface by a distance lo. Your Answer should look like the following format, you must find the constant C. a G=C- p d E