The amplitude of magnetic field in an electromagnetic wave...

The relation between the electric field and magnetic field is given by

${E}_{0} = c{B}_{0}$.

The given data is

${B}_{0} = 6 \times {10}^{- 7}T$

$c = 3 \times {10}^{8}m{s}^{- 1}$

Thus, the maximum value of the electric field is

${E}_{0} = \left(3 \times {10}^{8}\right) \times \left(6 \times {10}^{– 7}\right) = 180V{m}^{- 1}$.