Chemistry / Unit 5 Chem 0767 short lesson, about 20 seconds
The Speed of Light as a Defining Constant
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The idea
The speed of light in a vacuum is a fixed defining constant, exactly 299,792,458 meters per second by international definition of the meter.
In practice
For any electromagnetic wave, multiplying its wavelength by its frequency always returns this same fixed speed, c = λν.
Where people slip
This speed is fixed by definition, not a measured value some future experiment could revise, unlike an ordinary physical property.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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