system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do some lights glow after being turned off?


Sometimes when you turn a light off it glows quite dimly, but it only happens with some lights, can anyone explain why this is?
gpt
There are multiple reasons.  Many lights have capacitors in them that store a charge.  Once it's turned off that charge will slowly discharge through the electronics resulting in it being lit dimly for a while.

Good quality lights should have a resistor in the circuit that will quickly drain this charge so it goes out immediately.

Another way is that sometimes the current through the wiring induces a slight current in nearby wires.  This can be enough to slightly power lights even when the switch is off.

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Another reason is that some lights like fluorescent bulbs, use phospors, a chemical that absorbs UV and then re emits it as visible light.  These phosphors slowly discharge that light once the UV light is turned off.  It's basically the same process as glow in the dark materials, but not as strong.