Concept:Electromagnetic waves are transverse waves, not longitudinal waves.
Explanation:Electromagnetic waves travel through space and carry energy from one place to another.
In a vacuum, they all travel at the same speed, which is the speed of light,
3×108 m/s.
Each electromagnetic wave consists of an electric field and a magnetic field oscillating perpendicular to each other.
Both fields are also perpendicular to the direction of wave propagation.
This makes electromagnetic waves transverse in nature.
Longitudinal waves, such as sound waves, have oscillations parallel to the direction of travel.
Therefore, the statement that electromagnetic waves are longitudinal is incorrect.
Option A, B, and D are all correct properties of electromagnetic waves.
Only option C is false.
Answer:The incorrect statement is C: They are longitudinal.