Topic: Machine Design
Which of the following is applied to brittle materials?
- A. Maximum principal stress theory
- B. Maximum principal strain theory
- C. Maximum strain energy theory
- D. Maximum shear stress theory
Answer: A. Maximum principal stress theory
Explanation: The Maximum Principal Stress Theory (Rankine Theory) assumes failure occurs when the maximum principal stress reaches the yield or ultimate strength. It neglects shear stress and the other principal stress. This theory is suitable for brittle materials under all loading conditions because brittle materials are characteristically weak in tension. It is not suitable for ductile materials because it ignores shear stress.