Show that cos 0 dw = , and deduce that E = B, where Eb is the black body radiation density in terms of frequency emitted normally from a surface, per unit area. Use Planck's law 2hv B(T) = c [ehv/kT1] - to derive the Stefan-Boltzmann law in the form E= Eb, dv=T where 2k c2h3 z dz ez - 1 x By evaluating the integral and using the values c = 2.998 108 m s, k = 1.381 x 10-23 J K-1, h = 6.626 10-34 J s, evaluate the Stefan Boltzmann constant .