Define strain energy. Write formula for the same

Explanation

**Step-by-Step Solution:**

1. **Definition of Strain Energy:**
Strain energy is defined as the energy stored in a material or body when it undergoes deformation due to applied forces. This energy is a result of the work done on the material when it is stretched or compressed.

2. **Understanding Deformation:**
Deformation refers to the change in shape or size of a body when subjected to external forces. This can include stretching, compressing, bending, or twisting.

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