Einstein's mass-energy paper was only three pages

How can light speed remain constant even when moving?

Imagine you're driving a car at high speed and turn on your headlights. You expect the light to slow down as it moves faster than your car, right?

Think of light as a universal speed limit that doesn't change, no matter how fast you're going. This idea is rooted in Einstein's theory of special relativity.

Example

If you were moving at 60 mph and your car's headlights emitted light, the light would still travel at the constant speed of light (c), not slower due to your motion.

Remember this

Einstein's insight is that light speed is constant, leading to revolutionary concepts like time dilation and mass-energy equivalence.

Text adapted from Wikipedia, licensed under CC BY-SA 4.0.

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