LEDs of more than 100% efficiency?

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Don
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LEDs of more than 100% efficiency?

http://www.physorg.com/news/2012-03-efficiency.html

http://prl.aps.org/abstract/PRL/v108/i9/e097403

http://science.slashdot.org/story/12/03/08/1833224/leds-efficiency-excee...

 

Not had time to read these yet, but I thought folks might be interested. A few of the slashdot comments are worth a laugh or two.

 

The numbers from my light tests are always to be found here.

https://spreadsheets.google.com/ccc?key=0ApkFM37n_QnRdDU5MDNzOURjYllmZHI...

dthrckt
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My thermodynamics professor told me that nothing is 100% efficient.

I would like him to explain how my dogs output ~120% of the mass provided for input. 

My best guess?  It has something to do with the amount of time they spend sleeping on the couch.

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Old-Lumens
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dthrckt wrote:

My thermodynamics professor told me that nothing is 100% efficient.

I would like him to explain how my dogs output ~120% of the mass provided for input. 

My best guess?  It has something to do with the amount of time they spend sleeping on the couch.

Now That's Funny!!Tongue Out

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dthrckt
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only because you're not the one 'measuring' with a shovel Wink

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newbie74
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I real, the flashlight will cool down with use...

The first thing that came to mind was BEER!

newbie74
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Wrote the comment about cooling without reading. And then I read that it only works at high temps. I'm a believer...

Vectrex
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It is using some of its material to achieve that. No fundamental laws of physics were harmed during that experiment. Back as you were...

... but some of the SD comments are funny indeed.:

"The first law of thermodynamic is...you do not talk about thermodynamics:)"

Fightclub for Physicists.... lol

Don
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dthrckt wrote:

My thermodynamics professor told me that nothing is 100% efficient.

I would like him to explain how my dogs output ~120% of the mass provided for input. 

My best guess?  It has something to do with the amount of time they spend sleeping on the couch.

 

Oxygen. As in the food gets oxidised. When they (or we) breathe - atmospheric oxygen gets used. Which is why a pound of chocolate can cause more than a pound of weight gain.

 

The numbers from my light tests are always to be found here.

https://spreadsheets.google.com/ccc?key=0ApkFM37n_QnRdDU5MDNzOURjYllmZHI...

MixoMaxo
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Don wrote:

dthrckt wrote:

My thermodynamics professor told me that nothing is 100% efficient.

I would like him to explain how my dogs output ~120% of the mass provided for input. 

My best guess?  It has something to do with the amount of time they spend sleeping on the couch.

 

Oxygen. As in the food gets oxidised. When they (or we) breathe - atmospheric oxygen gets used. Which is why a pound of chocolate can cause more than a pound of weight gain.

what about oxygen plus 2 of hydrogen? xD

Ledsmoke
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I think we can see this effect when soldering XML emitters.

I often wondered why they light up ever so lightly when I solder the tabs. Always thought it was leak current from the soldering iron. But I just tried to measure it with my DMM - nothing. Then because I might be doing it wrong or the current is too low I tried it with a gas soldering iron. Same thing. Lights up ever so lightly. 

But cool that science also know it now. 

~ Ledsmoke ~

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WastedNihilist
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Ledsmoke wrote:

Always thought it was leak current from the soldering iron. But I just tried to measure it with my DMM - nothing. 

That made me laugh. Bring to mind trying to measure the lady with my ddm.

Vectrex
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Is she DC or AC? Which polarity if DC?