Q.The speed of electromagnetic waves in vacuum is

The speed of an electromagnetic wave in any medium is v = 1/√(με). Here με = (2μ₀)(ε₀/2) = μ₀ε₀, so v = 1/√(μ₀ε₀), the free-space value.

This is a core NCERT/CBSE-aligned Class 12 Physics result on electromagnetic waves.

Step 1 — general formula: In a medium of permittivity ε and permeability μ, v = 1/√(με).

Step 2 — substitute the given values: ε = ε₀/2 and μ = 2μ₀, so …

Maxwell's equations predict electromagnetic waves travelling in vacuum at speed c = 1/√(ε₀μ₀), which matches the measured speed of light.

From Maxwell's wave equation for electromagnetic waves in free space, the speed of propagation comes out to be c = 1/√(ε₀μ₀), where ε₀ is the permittivity and μ₀ the permeability of free space. Nu …