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Physics

Electromagnetic Waves

Quick fact

The speed of light in a vacuum—approximately 300,000 kilometers per second—is not just a speed limit for light; it's a fundamental constant that emerges directly from the properties of electric and magnetic fields in space.

Why this is interesting

You can't see them, but your phone, radio, and even your eyes rely on waves that travel through empty space. How can a wave exist where there is nothing to wave?