speed of light (redirected from Speed of light in vacuum)

speed of light

All electromagnetic radiation, including light, radio transmission and electricity, travels at approximately 186,000 miles (300,000 kilometers) per second; more than seven times around the equator in one second. More precisely, the speed is 299,792,458 meters per second in a vacuum.

Never Fast Enough!
This inherent speed of Mother Nature is why computers work so fast. Within the tiny chip, electricity has to flow only a couple of millimeters, and, within an entire computer, only a few feet. Yet, as fast as that is, it is never fast enough. There is resistance in the lines, which slows down the current, and even though transistors switch in billionths of a second, scientific and multimedia applications are always exhausting the fastest computers.

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speed of light [′spēd əv ′līt]

(electromagnetism)

The speed of propagation of electromagnetic waves in a vacuum, which is a physical constant equal to exactly 299,792.458 kilometers per second. Also known as electromagnetic constant; velocity of light.