#c = 3.00 x 10^8#m/s (the speed of light in a vacuum) #lambda# = wavelength in meters. #nu# = frequency in Hertz (Hz) or #1/s# or #s^-1#. So basically the wavelength times the frequency of an electromagnetic wave equals the speed of light. FYI, #lambda# is the Greek letter lambda , and #nu# is the Greek letter nu (it is not the same as a v). To find wavelength (#lambda#), the equation is manipulated so that #lambda = c/nu#. EXAMPLE PROBLEM.