Question

Which statement is correct about the speed of electromagnetic waves in a vacuum?

Answer 1

Explanation:

Speed of electromagnetic wave in vacuum is 1μ0ε0=c, where c is the speed of light. As we go from gamma rays to radio waves frequency decreases and wavelength increases thereby maintaining the product constant. Therefore, option c) is the correct option.

Answer 2

Electromagnetic waves travel at the speed of light (300,000,000 meters per second) in a vacuum.

Explanation:

• An electric and magnetic field do not require any medium to exert their effect.
• Hence in the presence of electric and magnetic field vectors that vibrate perpendicular to each other and receive disturbances EM waves travel in vacuum.
• Electromagnetic waves are just an observed phenomenon.
• The speed of electromagnetic waves will be different in glass than in water in air.
• The speed of a wave is often calculated as the product of frequency and wavelength.