what is the numerical value of it?
As a dimensional physical constant, the numerical value is different for different unit systems.
Speed of light
As a dimensional physical constant, the numerical value of is different for different unit systems.
who discovered the speed of light in a vacuum Witelo
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Speed of light [SEP] Numerical value, notation, and units
As a dimensional physical constant, the numerical value of is different for different unit systems. In branches of physics in which appears often, such as in relativity, it is common to use systems of natural units of measurement or the geometrized unit system where . Using these units, does not appear explicitly because multiplication or division by1 does not affect the result.