ERRATA for homework number 2, 2170

Problem 4: I want both the energy and the momentum of the outgoing electron.

Problem 5b: I gave you the wrong formula for the long wavelength limit of
the Plank distribution (I gave you power/area, rather than energy/volume,
which differ by a factor of c, as well as a geometrical factor)

The formula you are trying to reproduce is 

I(lambda,T) = (8 Pi k T)/lambda^4    d lambda


Computer problem: You may notice, depending on what units you choose to
express your intensity in, that MMA doesn't like to plot very small
numbers.  Perhaps you should RESCALE your numbers so their numerical
value is not so small...