Strain Formula - Definition, Derivation, Solved Examples

Strain Formula: Strain, in the context of materials, refers to the deformation that occurs when an object or material experiences an external force. This deformation can be a change in shape, size, or both. Imagine stretching a rubber band or compressing a spring; these actions result in strain, and it's the measurement of this strain that allows engineers and scientists to understand how materials behave under different conditions.

Strain Formula and Derivation

Strain (ε) = Change in Length (ΔL) / Original Length (L)

Types of Strain

1. Normal Strain:

2. Shear Strain:

3. Volumetric Strain:

Also Check - Relativistic Doppler Effect Formula

Stress-Strain Curve

Also Check - Heat Input Formula

Things to Remember

Also Check - Cell Potential Formula

Sample Questions Solved Of Strain Formula

1. Example 1: Calculating Normal Strain

Solution:

2. Example 2: Stress-Strain Curve Analysis

Solution:

3. Example 3: Shear Strain Calculation

Also Check - Normal Force Formula

Solution:

Shear strain (γ) = (0.03 m) / (Original side length) = (0.03 m) / (Original side length)

4. Example 4: Volumetric Strain in a Liquid

Solution:

Volumetric strain (ε_v) = (480 mL - 500 mL) / 500 mL = -0.04 or -4%

5. Example 5: Combined Normal and Shear Strain

ε_total = √(0.02² + 0.01²) = √(0.0004 + 0.0001) = √0.0005

ε_total ≈ 0.0224 or 2.24%