JEE Physics
JEEPhysicsElectromagnetic WavesClass 12

What does “Speed and field ratio” actually mean in Electromagnetic Waves, and why does it matter for JEE?

In vacuum all electromagnetic frequencies travel at c. For a plane wave E_0/B_0 = c; frequency changes photon energy and wavelength, not vacuum speed.

In simple words: In vacuum all electromagnetic frequencies travel at c. For a plane wave E_0/B_0 = c; frequency changes photon energy and wavelength, not vacuum speed. Getting Speed and field ratio clear matters because JEE questions on Electromagnetic Waves usually test this idea directly, not just a formula you memorised.

Key point

Speed and field ratio

Common mistake

claiming gamma rays travel faster than radio waves in vacuum.

Memory tip

same vacuum speed, different frequency and wavelength.

Tap to watch or see it right here — the app stays open (it only opens a quick search if nothing embeddable is found).

More on Electromagnetic Waves