Question 21:
easy
Consider the following statements for EM wave travelling in free space:
a. They are longitudinal in nature.
b. EM waves of different frequency have different speed in vacuum.
c. The average energy density associated with electric field is equal to energy density associated with magnetic field.
The correct statement(s) is/are
Electromagnetic waves are transverse in nature, and all EM waves travel with the same speed in a vacuum. The average electric energy density is equal to the average magnetic energy density, so only statement c is correct.