As light propagates through a vacuum, an electric field and a magnetic field are present. These fields

Step-by-step solution

Light is an electromagnetic wave. In an electromagnetic wave propagating through a vacuum, the electric field E and magnetic field B are mutually perpendicular to each other and both are perpendicular to the direction of propagation of the wave. The variations of the electric and magnetic fields are given by E = E ₀ ( t - kx) and B = B ₀ ( t - kx) . Since the fields vary sinusoidally with time, they do not remain constant. The average value of a sinusoidal function over a complete cycle is zero. Therefore, the aver