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Old June 26th 07, 10:50 PM posted to rec.aviation.piloting
RST Engineering
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Default 31 Days till OSH

Let's take ten watts from a battery or from the wall plug.

A light bulb (just for illustration sake, don't take the numbers as gospel)
spends 9.9 of those watts generating heat and 0.1 of the watts generating
light.

An LED spends 9 of those watts generating heat and 1 of those watts
generating light. The LED is therefore about ten times as efficient as a
light bulb.

However, the light bulb has about five or six square inches over which to
get rid of the 9.9 watts of heat (although the bulb is still very hot) while
the LED has less than a quarter of a square inch (without a heat sink) to
get rid of the 9 watts. Which one do you think will get hotter?

Jim

--
"Life is not a journey to the grave with the intention of arriving safely in
a pretty and well preserved body, but rather to skid in broadside,
thoroughly used up, totally worn out, with chocolate in one hand and wine in
the other, loudly proclaiming 'WOO HOO What a Ride!'"
--Unknown


"Jose" wrote in message
et...

And, [LED lights] are going to get hotter than
billy blue blazes unless you keep airflow over them.


Moreso than the edison invention? If so, where's the efficiency coming
from?

Jose