Question

All the failure theories give nearly the same results when

• (A) and (B) only
• (B) only
• (C) only
• (A) only

Hint:

When one principal stress is significantly larger than the others, most failure theories give similar results.

Answer 1

The Correct Option is A

Step 1: Understand the conditions for failure theories.
The different failure theories (like Maximum Normal Stress, Maximum Shear Stress, etc.) give nearly the same results under certain conditions. Specifically, when one of the principal stresses is much larger than the others or when shear stresses are dominant. Step 2: Conclusion.
Failure theories are similar when principal stresses are unequal, particularly when one of them is much larger than the others, and when shear stresses are present. Final Answer: \[ \boxed{\text{(A) and (B) only}} \]