From your list in Problem 1.2, select two devices, or parts of those devices, that you can represent as closed systems. Sketch each device, show the system boundary as a dotted line, and label as needed to make your sketch intelligible. Discuss why your  choice encloses a closed system.

 Problem 1.2

Device Toaster Air conditioner Light bulb Clothes iron Refrigerator Form of Energy Input Electrical energy Electrical energy Electrical energy Electrical energy Electrical energy Form of Energy Output Heat transfer from the hot metal strips Heat transfer from cold to hot regions Heating of bulb by electrical resistance of the filament Heat transfer Heat transfer to kitchen