How Did Ancient People Measure the Speed of Light?

Long ago, people didn't have fancy clocks or lasers, but they were still curious about light. One smart guy named Alhazen figured out that if you cover a lamp with a plate and make a tiny hole, the light would come through like a tunnel. He watched how long it took for the light to reach his eyes, that's how he guessed the speed of light!

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Alhazen watched light travel through a tunnel like watching someone walk from one end to another.
It’s like waiting for your friend to come through a small window, you know they’re coming, but it takes time.
He measured the delay in light just like we count seconds when we see lightning and then hear thunder.

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Categories: History · Ancient Science,Light,Measurement