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Fridge experiment

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This may be a bit basic for the physist on this forum, but its causing arguments amoung my colleagues and I. I think I know the answer but am unable to prove it...

 

Consider the following experiment…

 

Two identical fridges with portable power sources are switched on in london and set to 5 degrees. A standard can of coke is placed in each. One of the fridges is transported to central antarctica. The fridges are then left switched on for 2 months. Robots inside the fridges then take the temperature of liquid in the cans.

 

The question is…

 

Will the cans be the same temperature? Or will they differ and if so how?

A fridge cannot create heat, and can only decrease the temp, so the fridge in central antarctica would be below zero after a while as the ambient temp is less than Zero. The coke in london woud have been stolen by your flatmate on day 3.

that's probably true;)

 

but yes, the fridge in Antarctica would be lower unless it had some really, really good insulation to keep heat and cold out..

I prefer the question of 'You have a fridge in a perfectly isolated room (powered from outside the room). You open the door. What change happens to a thermomiter in the room?'

the first thing that would happen is that the temperature would drop to the mean temperature of the room and fridge (assuming the fridge was already cold) then it would rise above the original mean temperature of the room-fridge system. as you pump power into the fridge.

Originally posted by Radical Edward

the first thing that would happen is that the temperature would drop to the mean temperature of the room and fridge (assuming the fridge was already cold) then it would rise above the original mean temperature of the room-fridge system. as you pump power into the fridge.

 

2nd law of thermodynamics.

 

How about a candle in a lift, that goes into freefall?

I am wondering if the light turns off when the door is shut in either of the two locations. That is the real question!

 

 

 

:D :lame:

 

I feel the temperatures would be the same in either fridge, but possibly the amount of run time and total power consumption of the fridge in London might be more.

 

If a third identical fridge was dropped onto the equator somewhere, would you also assume that the temperature would be even warmer there?

 

That doesnt make any sense to me. The refrigerator doesnt know where it is and could care less where it is. It cools to 5 degrees regardless of ambient temperatures. It just may work a little more or less depending on location. Right? :confused:

NO I AM NOT GOING TO WASTE MY LIFE PONDERING ABOUT A FRIDGE IN ANTARTICA!!!!!

Originally posted by NavajoEverclear

NO I AM NOT GOING TO WASTE MY LIFE PONDERING ABOUT A FRIDGE IN ANTARTICA!!!!!

 

Why do you consider it a waste?

It would also depend on what brand of fridge.

 

On a side note, the sub zero temp. in antartica would effect the electrical circuts in the fridge in antartica, thus changing the temp of that fridge.

 

What I would like to know is, what would the temp of the coke be if you flipped the power of the fridge on and off consecutivley for three months straight be, then if you just left it on.

Why do you consider it a waste?

 

Dear lord is there any hope left in the world?

Originally posted by NavajoEverclear

 

Dear lord is there any hope left in the world?

 

In the world? Not a chance. All hope lies in space.

Originally posted by NavajoEverclear

Dear lord is there any hope left in the world?

 

I heard that doing anything that required intellect was a waste of time :cool:

Originally posted by MrL_JaKiri

 

I heard that doing anything that required intellect was a waste of time :cool:

 

So what your saying is that all of earths hope lie in this site. Thats depressing.

excuse me, so do you mean to say that discussing antartican refrigerators is the best use of my intellect? If you were best using your intellect you would be doing something much more useful than posting on this site. I speak the truth, why does not anyone hear? And yet i know i could make up lies so people will agree with me, but i have a little more integrity than that.

Answering a question like this shows an understanding of the processes involved and thus helps you to do 'something much more useful'. Perhaps not. Personally, I just like to answer them, and I know I work better fulfilled than bored.

This may not be the best use of my intellect, but it is a good one. I am helping out all those who are ignorant, by giving them information.

Originally posted by NavajoEverclear

excuse me, so do you mean to say that discussing antartican refrigerators is the best use of my intellect? If you were best using your intellect you would be doing something much more useful than posting on this site. I speak the truth, why does not anyone hear? And yet i know i could make up lies so people will agree with me, but i have a little more integrity than that.

 

This is from a kid who asked us ways to break into Area 51. :rolleyes:

Originally posted by superchump

This is from a kid who asked us ways to break into Area 51. :rolleyes:

I fully support any and all efforts he might make in that direction.

 

I'd pay the air fare just to come and watch, in fact. Anybody got a video camera with a big zoom lens?

Originally posted by Sayonara³

I fully support any and all efforts he might make in that direction.

 

I'd pay the air fare just to come and watch, in fact. Anybody got a video camera with a big zoom lens?

 

And I'd laugh as 20 armed soldiers swarmed him five minutes after he crossed the property line. :D

Originally posted by MrL_JaKiri

 

2nd law of thermodynamics.

 

How about a candle in a lift, that goes into freefall?

 

it would just go out wouldn't it? as there is no 'up'

Originally posted by superchump

 

And I'd laugh as 20 armed soldiers swarmed him five minutes after he crossed the property line. :D

 

And I'd run out there to help him get away from the armed soldiers. At least as much help I could while laughing. That would be a funny sight. Unless they shot of course. Then it would sad.

  • 1 month later...

the candle would indeed just go out as it consumed all the oxygen local to it, prior to this the flame would be sperical. the candle would re ignite when moved however or in a gentle draft :)

 

Fire needs Fuel, heat and oxygen, remove any one and the fire goes out (in this case the local oxygen) the fuel and the heat would still be present though, eventualy however the heat would be lost as black body radiation eventualy. but not fast enough to provide some interesting results :)

What if you dumped the can of coke from antartica on the candle falling down the lift?.....While turning the lights on and off simultaneously......

I expect you`de look really rather silly doing it :)

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