We just studied E.M. waves; May I assume that whenever we flip a switch, an E.M. wave is produced? -for example, flipping a light switch- If a wave is produced, how does it break off? We have a closed circuit. Does it break off & propogate near the Emf source? Ps. I am so so confused. I also wondered how the glow of a filament- which is electric energy transforming into thermal energy via collisions between moving electrons and the atoms of the wire- have anything to do with perpendic. electric and magnetic fields propogating through space. glow of filament = light = E.M. wave? Don't see how collisions of electrons & atoms translate into propogating perpendicular electric and magnetic fields.