Parasitic Capacitive Coupling

[jmatejka]

I came across an interesting picture. Many of us know about fluorescent lights being able to illuminate under high tension power lines. My first thought of mechanism for this was “induction”, however it was suggested that this is done by the Electric field not the Magnetic, (B).

The fluorescent bulbs in many different pictures point perpendicular direction to the wires, not parallel as induction would dictate. I assume the changing Electric field is capacitively causing the bulb to illuminate. Make Sense? Seems to make sense to me. Seems like a good description of the E field at work. Thanks, John

 

[Valerie Park]

.Yes, John, that does make sense. The electric field created by the high tension power lines is strong enough to induce a current in the fluorescent bulb, which in turn causes it to illuminate. This is known as capacitive coupling and is similar to the way induction works, but with the electric field instead of the magnetic field.