On a hot summer day we want to cool our room by opening the refrigerator door and closing all the windows and doors. Will the process work?
No, This will rather cause an increase in room temperature than decreasing it.
The refrigerator is a device which takes the heat from the refrigerator cabin and expels it outside the fridge, with the help of external work. If we keep the refrigerator door opened while keeping the windows and doors closed, the refrigerator will take in the heat from the room and expel it into the room itself. Since no instrument can work with 100% efficiency, the loss in the electrical energy of the fridge will dissipate as heat, and this along with the heat after refrigeration, will be expelled into the room itself. Hence, in a room with an opened fridge door, it will expel more heat than it takes in from the room.
Since all the windows of the room are closed, opening the refrigerator door will result in an increase in the room temperature instead of decreasing it.
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