Yeah, the above statement is somehow true, and I mentioned correctly. That is you can die of extreme heat and not extreme cold. Not immediately but you will Definitely. So being an engineer is no doubt a tough task.The path is very challenging but no doubt it’s very interesting too. You might have seen a lot of pictures like this on social media. Or even you to have thought of this Didn’t You..?? When the question is asked what is the room temp when you open your fridge in the room then most of the answer is the room temp will be decreased.But sadly the answer is wrong.It is completely opposite that is the temperature of the room will be increased. So let’s check the reason behind this heating effect in the thermodynamic point of view (Yeah thermodynamics).
Ok so from now it’s gonna be a little techy below here but No problem. After reading this article, one thing is sure that whenever you will see a picture like this. You are definitely gonna remember our blog. is completely opposite that is the temperature of the room will be increased. So let’s check the reason behind this heating effect in the thermodynamic point of view (Yeah thermodynamics).
Yeah, so the answer what you were thinking is not true. It is completely opposite that is the temperature of the room will be increased. So let’s check the reason behind this heating effect in the thermodynamic point of view (Yeah thermodynamics, told you).
In many ads, posters its seen that in summer people open their refrigerator door to cool the room.But the concept is completely wrong.Before we start let’s know some facts about the refrigerator in thermal engineering aspects.
In thermodynamics, the refrigerator is treated as a work consuming device which extracts heat from its cabin and throws the heat to the surrounding. According to Clausius, it is impossible to transfer heat from a low temp region to a high temp region. So the fridge takes some electrical energy to maintain the heat flow from low temp region i.e. its cabin to high temp region i.e. the surrounding as the temp of the cabin is always very less than to the normal room temp.
Fig shows that fridge extracts the Q2 amount of heat from the cabin which has to be maintained at T2 temp, and the heat Q1 is thrown to the surrounding which has a temp of T1 and T1 is greater than T2. It is done with the help of W amount of electrical work.
So after conserving the total energy goes through the refrigerator we have the equation,
I.e. Heat rejection to the surrounding is greater than that of heat removed
When you open your fridge door then similarly
The heat rejection to the room will be greater than the heat removed from the room by the fridge. Therefore the net heat flow is from the fridge to the room.
Maybe the temp near the door low, but the overall temp of the room will considerably increase.
So next time don’t open the fridge in summer to cool the room, it will be completely wastage of electricity and instead of it use an air conditioner.