A load of 4.0 kg is suspended from a ceiling through a steel wire of length 20 m and radius 2.0 mm. It is found that the length of the wire increases by 0.031 mm as equilibrium is achieved. Find Young modulus of steel. Take `g=3.1pims^-2`

Explanation

To find the Young's modulus of steel, we can follow these steps:

### Step 1: Identify the given values
- Load (mass), \( m = 4.0 \, \text{kg} \)
- Length of the wire, \( L = 20 \, \text{m} \)
- Radius of the wire, \( r = 2.0 \, \text{mm} = 2.0 \times 10^{-3} \, \text{m} \)
- Change in length, \( \Delta L = 0.031 \, \text{mm} = 0.031 \times 10^{-3} \, \text{m} \)
- Acceleration due to gravity, \( g = 3.1 \, \text{m/s}^2 \)
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