Tesla (unit) One tesla is equivalent to: One tesla is equal to 1 V·s/m. This can be shown by starting with the speed of light in vacuum, "c" = (εμ), and inserting the SI values and units for "c" (), the vacuum permittivity ε (), and the vacuum permeability μ (). Cancellation of numbers and units then produces this relation. For the relation to the units of the magnetising field (ampere per metre or Oersted), see the article on permeability. Tesla (unit) The tesla (symbol T) is a derived unit of the magnetic field strength (also, magnetic flux density) in the International
Spectral flux density In a region in which the material is uniform and the radiative field is isotropic and homogeneous, let the spectral radiance (or specific intensity) be denoted by , a scalar-valued function of its arguments , , , and , where denotes a unit vector with the direction and sense of the geometrical vector from the source point to the detection point , where denotes the coordinates of , at time and wave frequency . Then, in the region, takes a constant scalar value, which we here denote by . In this case, the value of the vector flux density at