Chapter 15, Problem 14Q

To determine

Why do the machine called“in-room air conditione” cannot cool the room?

Answer to Problem 14Q

Solution:

The machine called“in-room air conditioner” cannot cool the room because there should be high temperature heat exhaust outside the room.

Explanation of Solution

The machine“in-room air conditioner” will remove the heat from the room ($Q_L\to$ Low temperature heat)as input to the machine. By thermodynamics second law there must be a high temperature heat exhaust ($Q_H$). But the inventors has named the machine as“in-room air conditioner” which means the exhausted heat is moved to heat sink in the room but continuously adding heat to the machine will make the machine warmer which further increases the room’s temperature so we can say that“in-room air conditioner” cannot cool the room.