Question

A copper wire of diameter 1.6 mm carries a current of 20 A. Find the maximum magnitude of the magnetic field $\overrightarrow{B}$ due to this current.

Answer 1

Here diameter = $1.6\times {10}^{-3}m$

$\therefore$ radius = $0.8\times {10}^{-3}m$

We know $B=\frac{{\mu }_{0}i}{2\pi r}$

$\frac{2\times {10}^{-7}\times 20}{0.8\times {10}^{-3}}=5mT$