Concepts

# Concepts

## Idea

The meter or metre (in European spelling) is a physical unit of length. It is defined by taking the fixed numerical value of the speed of light in vacuum $c$ to be $299792458$ when expressed in the unit $m\cdot s^{-1}$, where the second is previously defined.

## References

See also

Last revised on April 2, 2019 at 19:58:37. See the history of this page for a list of all contributions to it.