Physics (AS & A Level) · Feb / March 2025 · Paper 12 · Question 31

A copper wire is 6.4 m long and has a resistance of 0.92 Ω. The resistivity of copper is 1.8 × 10⁻⁸ Ω m. What is the diameter of the wire?

1. A5.7 × 10⁻⁵ m
2. B1.0 × 10⁻⁴ m
3. C4.0 × 10⁻⁴ m
4. D7.1 × 10⁻⁴ m

As printed in the paper