1. The problem statement, all variables and given/known data 2. Relevant equations Poynting's Theorem S = 1/μ0 (E x B) Momentum = p = μ0ε0 ∫ S dτ 3. The attempt at a solution My strategy was to treat the hollow sphere as a point charge (by Gauss' Law), so E = 1/4πε0 Q/a2. I believe the magnetic field would be B = 2/3μ0M (where M is the magnetic dipole moment per unit volume). For part A, would this be the correct total electromagnetic momentum if I used the formula stated above and the relevant E and B fields. Also, do I have the E and B field formula's correct?