Question

In an elastic solid, the work done by an external force to produce strain is $800\text{J}$. If the external force is removed, then the elastic potential energy of the solid will be -

• A. $800\text{J}$
• B. $400\text{J}$
• C. $200\text{J}$
• D. $0\text{J}$

Answer 1

The correct option is D $0\text{J}$

We know that, for perfectly elastic material, work done by an external force to produce strain is stored as potential energy of the material.
Potential energy is due to deformation in the shape and size of the body.

As the external force is removed, the elastic material regains its shape and size.
Therefore, no energy will be stored as elastic potential energy.