A plane electromagnetic wave having a frequency ν = 23.9 GHz propagates along the positive z-direction in free space. The peak value of the electric field is 60 V/m. Which among the following is the acceptable magnetic field component in the electromagnetic wave?
Options

Question

A plane electromagnetic wave having a frequency ν = 23.9 GHz propagates along the positive z-direction in free space. The peak value of the electric field is 60 V/m. Which among the following is the acceptable magnetic field component in the electromagnetic wave?

Options

G1 Physics · Accepted Answer

In free space B₀=E₀/c=60/(3×10⁸)=2×10⁻⁷ T. For propagation along +z, E⃗×B⃗ must point along +z, and the phase must have the form kz−ωt (up to an overall sign). These conditions match option C.