have you ever wondered how your refrigerator gets things cold? i have. turns out, refrigerators use the same physics to cool things as air conditioners, dehumidifiers, and many other household devices. what happens is there is a compressor, two coils of tubing, and an aperture; all working together to make your beverages so damn frosty. if you listen to a refrigerator, what you probably hear is the compressor. the compressor uses electricity to create pressure in the external coil, letting it expel energy as heat, then the gas flows through the aperture and expands, soaking up the same amount of energy from inside the fridge as it just expelled through the external coil. this process is repeated, and the heat is effectively pumped out of the fridge. this principle can be demonstrated with a aerosol can. when you push the nozzle down for a few seconds, the can gets cool. this is because it soaks up the energy from your hand as the gas expands, much in the same way the gasses do in the fridge.