The fatigue test is used to design components subjected to varying load. It experimentally determines endurance limit of material.

Shear stress = 10kN / 100mmx100mm = 1 N/mm² = 1MPa.

The maximum torque transmitted by a circular solid shaft is obtained from maximum shear stress induced at outer surface of solid shaft and given by T = ?D³/16 x normal stress,
So, normal stress = 16T/?d³.

Creeping is phenomenon of slow growing strain under a stress for a period of time.

Elongation in section 1 = 100,000 x 100 / 100000 x100 = 1
Elongation in section 2 = 100,000 x 100 / 100000x 200 = 0.5
Total elongation = 1 + 0.5 = 1.5mm.

Shear stress makes body to shear off across section. It is tangential to area over which it acts. The corresponding strain is shear strain.

The stress = P/A
Where P = 35000N and A is respective cross section area of sections.

The stress = P/A
Where P = 1000N and A is respective cross section area of sections. Here stress will be equal in both sections as dimensions are same.

In a ductile material, true stress at fracture will be higher ultimate stress.

We know that due to temperature changes, dimensions of material change. If se changes in dimensions are prevented partially or fully, stresses are generated in material and if changes in dimensions are not prevented, re will be no stress set up. (Zero stresses).
Hence cylindrical rod Is allowed to expand or contract freely.
So, ?_x = 0 and ?_y = 0.