second radiation is a fundamental constant in the Physico-chemical category of constants.  The second radiation constant, c2, is used in Planck's law. It has the SI units of metres kelvin. It is given by the equation:

c_2 = hc / k

where h is the Planck constant, c is the speed of light and k is the Boltzmann constant. Its value is 1.438775x10^-2 m K.

Planck's law gives the radiation intensity emitted by a black body for a given frequency and temperature.

Notes

Value  1.438 7770 x 10-2 m K

Standard uncertainty  0.000 0013 x 10-2 m K

  Relative standard uncertainty   9.1 x 10-7

Concise form  1.438 7770(13) x 10-2 m K