1. The problem statement, all variables and given/known data Calculate electric field and magnetic field produced by radiation emitted by a 100 W bulb at a distance of 1 m if radiation efficiency is only 5%. 2. Relevant equations 3. The attempt at a solution I only know how to find intensity due to the bulb: I = P/4πr2 = 5/4π W/m2 I have absolutely no idea how to find the electric and magnetic field from that information. I do know that B = E/c, so I just need to find one of those.