Canned Air Hack
As you use a can of air, the power of the air stream slowly diminishes.
Have you ever noticed that the can gets colder as you use it?
This happens because temperature and pressure are related, when volume is constant.
This is part of the ideal gas law:
As air leaves the can, the pressure drops. Because the volume of the can is constant, temperature drops, and eventually, you may notice frost or ice on the outside of the can!
Heat is energy, and cold is simply the lack of heat energy (just as a shadow is the absence of light).
How do I get a few more blasts out of my frozen can of air?
You COULD wait until the can absorbs heat from the ambient air. “Room temperature” air is typically 75 F, and air is a decent conductor, but not as good as liquid. It might take a while!
You could run the can under some warm (LESS than 100 F) water for a few seconds.
This washes away the ice / frost on the outside of the can, and because water (and most liquids) are such a good conductor of heat, the can rapidly absorbs heat energy from the liquid, thus increasing the pressure of the gas inside the can.