Question

The property which is not of an electromagnetic wave travelling in free space is that :

• A. they are transverse in nature.
• B. the energy density in electric field is equal to energy density in magnetic field.
• C. they travel with a speed equal to $\frac{1}{\sqrt{\mu_0\epsilon_0}}$.
• D. they originate from charges moving with uniform speed.

Answer 1

Answer: (D)

they originate from charges moving with uniform speed.

Answer 2

Electromagnetic waves are generated by charges undergoing acceleration, not by charges moving with uniform speed. All other properties are characteristics of electromagnetic waves:
- Energy densities of electric and magnetic fields are equal.
- Their speed is $\frac{1}{\sqrt{\mu_0 \epsilon_0}}$.
- They are transverse waves.