The resistivity of copper is approximately `1.67xx10^(-8)Omegam`.
Calculate the electrical resistance of a hollow tube made of copper of external radius 20 cm and length 20 cm . The thickness of copper is 50 mm .

Explanation

To calculate the electrical resistance of a hollow copper tube, we will follow these steps:

### Step 1: Convert Given Measurements to SI Units
- **External Radius (R2)**: 20 cm = 20 × 10^(-2) m = 0.20 m
- **Thickness**: 50 mm = 5 cm = 5 × 10^(-2) m = 0.05 m
- **Length (L)**: 20 cm = 20 × 10^(-2) m = 0.20 m

### Step 2: Calculate Internal Radius (R1)
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