28-02-2007, 06:48 PM
Actually, it's because lightbulbs heat up the wire inside them, the heat gets radiated, it feels hot.
Light bulbs also give out photons (this is how CRT TVs/monitors work)
Using filament lamps, a perfectly efficient light is impossible (then again, a perfectly efficient anything is impossible). filament bulbs are about 20/25% efficient- yeah, from your 50W bulb you get 10W of usable light. Filament bulbs are just about as efficient as tehy'll ever be, LED's hold the key to efficient lighting of the future, though flourescent lighting is also pretty good.
Light bulbs also give out photons (this is how CRT TVs/monitors work)
Using filament lamps, a perfectly efficient light is impossible (then again, a perfectly efficient anything is impossible). filament bulbs are about 20/25% efficient- yeah, from your 50W bulb you get 10W of usable light. Filament bulbs are just about as efficient as tehy'll ever be, LED's hold the key to efficient lighting of the future, though flourescent lighting is also pretty good.