I've noticed something interesting: high voltage (HV) lines can produce enough voltage to power an incandescent light bulb, but oddly enough, the bulb doesn't glow when it's directly under a HV line, unlike fluorescent bulbs. Can someone explain why this happens?
2 Answers
Yep, exactly! Incandescence is all about heating a filament until it glows, but under a HV line, the current isn't sufficient to heat it up. Fluorescent lights work differently—as the electric field excites the gas within them, they can emit light without needing as much current. It's a fascinating distinction!
It's all about current, not just voltage! HV lines can produce high voltage, but they have very high impedance, which means they can only deliver a small amount of current. An incandescent bulb needs a lot of current to produce light since it works by heating a filament. On the other hand, fluorescent bulbs require much less current because they rely on gas excitation to emit light, which is why they glow under those lines. So, while the voltage might be there, the current isn't enough for the incandescent bulb to light up.
That makes a lot of sense! So basically, it's the difference in how these bulbs produce light that explains the issue, right?