CAPE Physics Unit 2 · 2011 · Paper 1 · Question Q13

A road is 15\text{ m} below a transmission line which carries an alternating current of peak value 100\text{ A}. The magnitude of the peak magnetic flux density at the road (due to the current in the transmission line) is

1. (A)1.33 \times 10^{-6}\text{ T}
2. (B)4.19 \times 10^{-6}\text{ T}
3. (C)1.26 \times 10^{-4}\text{ T}
4. (D)1.18 \times 10^{-2}\text{ T}