Question

In case of linearly polarised light, the magnitude of the electric field vector.

• A. Does not change with time
• B. Varies periodically with time
• C. Increases and decreases linearly with time
• D. Is parallel to the direction of propagation

Answer 1

Answer: (B)

Varies periodically with time

In any type of light whether polarised or unpolarised, the magnitude of electric field vector always varies periodically with time.
Actually the change in electric field vector gives rise to periodically changing magnetic field.