If resistance `R_1` in resistance box is `300 Omega` then the balanced length is found to be `75.0 cm` from end `A`. The diameter of unknown wire is 1 mm and length of the unknown wire is `31.4 cm`. Find the specific resistance of the unknown wire

Explanation

To find the specific resistance (resistivity) of the unknown wire, we will follow these steps:

### Step 1: Understand the given data
- Resistance in the resistance box, \( R_1 = 300 \, \Omega \)
- Balanced length from end A, \( L_A = 75.0 \, \text{cm} \)
- Length of the unknown wire, \( L = 31.4 \, \text{cm} = 0.314 \, \text{m} \)
- Diameter of the unknown wire, \( d = 1 \, \text{mm} = 1 \times 10^{-3} \, \text{m} \)

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