Q. The velocity of electromagnetic radiation in a medium of permittivity ε₀ and permeability μ₀ is given by
A) √(μ₀/ε₀)
B) √(ε₀/μ₀)
C) √(μ₀ε₀)
D) 1/√(μ₀ε₀)
Explanation
[Solution from source] Maxwell's equations give the wave speed v = 1/√(με); with ε₀ and μ₀ this is c = 1/√(μ₀ε₀) ≈ 3 × 10⁸ m/s. √(μ₀ε₀) is its inverse, with dimensions of time per length, and √(μ₀/ε₀) is the impedance of free space (in ohms), not a speed. Answer (4).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.