Question

The strain energy stored in a body with sudden load application, the maximum stress induced is twice the stress induced when:

1. the same load is applied suddenly.
2. the same load is applied gradually.
3. the same load is applied by an impact.
4. the torque of same load is applied.

Answer 1

Correct Answer - Option 2 : the same load is applied gradually.

Concept:

The maximum stress due to a suddenly applied load is twice the stress produced by a load of the same magnitude applied gradually

Mathematically, 

In case of a bar, if A is the cross-section of the bar, and it is placed vertically with one end attached to ceiling 

Then, 

\(\sigma = \frac{P}{A}\)  ........................(Load P is applied gradually)

\(\sigma = \frac{{2P}}{A}\)  .........................(Load P is applied suddenly)