In a plane electromagnetic wave propagating in space has an electric field of amplitude 9 × 103 Vm−1 , then the amplitude of the magnetic field is

2.7 × 1012 T 9.0 × 10−3 T 3.0 × 10−4 T 3.0 × 10−5 T

3.0 × 10−5 T

$B_0=\frac{E_0}{c}=\frac{9×10^3}{3×10^8}=3 × 10^{-5} \, T$