Question

When light propagates in vacuum there is an electric field and a magnetic field. These fields

• A. are constant in time
• B. have zero average value
• C. are perpendicular to the direction of propagation of light.
• D. are mutually perpendicular

Answer 1

Answer: (B), (C), (D)

have zero average value
are perpendicular to the direction of propagation of light.
are mutually perpendicular

When light propagates in vacuum there is an electric field and a magnetic field which has zero average value. They are perpendicular to each other and also perpendicular to the direction of the propagation of light.