An electromagnetic wave in vacuum has an electric field amplitude of $6.0 \times 10^2$ V/m. Set the magnetic field amplitude, in units of $10^{-6}$ T, using $c = 3.0 \times 10^8$ m/s.

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$B = E/c = 6.0\times10^2/3.0\times10^8 = 2.0\times10^{-6}$ T. The magnetic amplitude is smaller by the enormous factor $c$, which is why the electric force dominates the interaction of light with matter.