Consider a single crystal oriented such that the slip direction and normal to the slip plane are at angles 50° and 55°, respectively, with the tensile axis. If the critical resolved shear stress is 10 MPa, cause the single crystal to yield? If not, what stress will be necessary?

Ahelical coil spring has a mean diameter of 50 mm, a wire diameter of 5.5 mm and is wound with a pitch of 10 mm. the spring steel has an ultimate strength of 1250 mpa. find the force needed to compress the spring solid and the wire stress in this condition. state whether the spring will return to its initial length.