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Q:

How fast does light travel?

A:

In a vacuum, the speed of light is 186,282 miles per second. This is equal to 299,792 kilometers per second or about 670,616,629 miles per hour.

Know More

Attempts to calculate the speed of light have been going on for centuries. Aristotle believed that light traveled instantaneously, but another ancient Greek scientist, Empedocles, believed that light must take time to travel because light is capable of movement. Albert Michelson used an apparatus with a beam of light on a rapidly rotating mirror to measure the speed of light. Albert Einstein calculated that no matter how quickly an observer moves, light travels at the same speed, and that the speed of light does not vary with time or location.

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Related Questions

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Electricity travels at the speed of light, which is 186,000 miles per second. This is because electricity is electromagnetic radiation just like light. Electricity is the flow of electrons through a conducting wire such as copper and aluminum.

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The speed of light is 186,282 miles per second. An object travelling at the speed of light would make approximately 7.5 rounds around the Earth in one second.

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When light travels in a vacuum, its speed is 186,282 miles per second. The fastest aircraft, which is the Boeing-43 scramjet, has a speed of 7,546 miles per hour. If these two speeds are compared, the jet's speed is approximately 0.0004 percent that of light.

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Light travels at 186,282 miles per second, or approximately 670,616,629 miles per hour, in a vacuum. As of 2014, it is assumed that no object that has mass can travel at or above this speed.