Question

A sinusoidal electromagnetic wave is propagating in a vacuum in the +z-direction.
If at a particular instant and at a certain point in space the electric field is in the +x-direction and has a magnitude of 3.40V/m, what is the magnitude of the magnetic field of the wave at this same point in space and instant in time?

Answer 1

Answer:

$1.13\times10^{-8} T$

Explanation:

$E_{o}$ = magnitude of electric field at the point in space = 3.40 Vm⁻¹

$B_{o}$ = magnitude of magnetic field at the point in space = ?

$c$ = speed of electromagnetic wave in vacuum = 3 x 10⁸ ms⁻¹

Magnitudes of electric and magnetic field are related to each other as

$c B_{o} = E_{o}\\B_{o} = \frac{E_{o}}{c} \\B_{o} = \frac{3.40}{(3 \times10^{8} )}\\B_{o} = 1.13\times10^{-8} T$