A steel rod 2.0 m long has a cross-sectional area of `0.30cm^(2)`. The rod is now hung by one end from a support structure, and a 550 kg milling machine is hung from the strain, and the elongation of the rod.

Explanation

To solve the problem of finding the elongation of a steel rod when a milling machine is hung from it, we can follow these steps:

### Step 1: Identify the given data
- Length of the steel rod, \( L = 2.0 \, \text{m} \)
- Cross-sectional area, \( A = 0.30 \, \text{cm}^2 = 0.30 \times 10^{-4} \, \text{m}^2 = 3.0 \times 10^{-5} \, \text{m}^2 \)
- Mass of the milling machine, \( m = 550 \, \text{kg} \)
- Acceleration due to gravity, \( g = 9.8 \, \text{m/s}^2 \)

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