Assignment:
"The magnetic field permeating a region of space represents stored energy. This energy is often quantified in terms of its density (magnetic energy per unit volume) given by B^2/(2*u) where u=4*pi X 10^(-7). Suppose an "X2" flare occurs within a volume of 10^12 km3 over a sunspot pair initially permeated by an average magnetic field strength of 1000 Gauss. Calculate the total magnetic energy in Joules stored in the volume before the flare occurs. "