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Chapter 15: 12Q (page 412)

Question:You are asked to test a machine that the inventor calls an 鈥渋n-room air conditioner鈥�: a big box, standing in the middle of the room, with a cable that plugs into a power outlet. When the machine is switched on, you feel a stream of cold air coming out of it. How do you know that this machine cannot cool the room?

Short Answer

Expert verified

The machine cannot cool the room because the heat addition will make the room warmer

Step by step solution

01

Understanding air conditioners 

In this problem, the inventor鈥檚 device called 鈥渋n room air conditioner鈥� is an air-conditioner type heat engine, andit will remove heat from the room.

02

Explanationfor the inventor’smachine about cooling the room                              

The machine made by the inventor is named an 鈥渋n-room air conditioner.鈥� It is a huge box placed in the middle of the room. It is connected to the power outlet through a cable.

By the law of thermodynamics, it can be said that there should be a greater temperature exhaust heat, which should be larger than the removed heat. In this condition, the addition of heat to the machine will make the room warmer.

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