Question

What is the velocity of electromagnetic wave in free space?

(a) c = √μ0ε0

(b) c = \(\frac {1}{\sqrt {\mu_0 \varepsilon_0}}\)

(c) c = \(\frac {1}{\mu_0 \varepsilon_0}\)

(d) c = μ0ε0

The question was asked during an interview.

The doubt is from Electromagnetic Waves topic in portion Electromagnetic Waves of Physics – Class 12

Answer 1

Correct choice is (b) c = \(\frac {1}{\sqrt {\mu_0 \varepsilon_0}}\)

Best explanation: The value of c is the same for all types of electromagnetic waves because the constants μ0 and ε0 do not depend on the frequency or wavelength of the electromagnetic waves. So, the velocity of electromagnetic wave in free space is given as:

c = \(\frac {1}{\sqrt {\mu_0 \varepsilon_0}}\).