Problem 24.3

24.3
We know that
$\frac{E}{B} = c$
Solving for B, we find
$B = \frac{E}{c}$
Substituting in our value for E, we have
$B = \frac{220}{3 \times 10^{8}}$
$B = 7.33 \times 10^{-7} T$