I have heard a lot about pressure. Heat air is less dense and also has low pressure, but I thought heat air has high pressure. I know that compressed waiting is walk to be hot, so wouldn"t it have actually high pressure?

We recognize that the air molecules in cold air move slower 보다 in warmth air, however there are much more of them pack closer together. So the possibilities of colliding are much more significant. Is that why cold air has actually high pressure?

This is a counter-argument because the molecule in hot air are farther apart however move faster so castle would additionally have a large chance of colliding, right?

I would certainly appreciate it if the gentleman or women who reply to this could answer all of my concerns if friend can, but any kind of reply would be appreciated.

Thanks, Gary

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The answer is nobody of the above. You have the right to have warm air that is lower pressure, higher pressure, or equal push to cold air. However, if you desire to emphasis on a solitary body of waiting (such together the air in a room, or wait in a balloon), we can talk about how changes impact pressure.

You are watching: Which has higher air pressure—warm air or cold air?

The an essential equation, together I.E.P. Mentioned in the comments is $PV=nRT$ where:

P is the pressure of the gasV is the volume the the gasn is the number of mols of gasR is the ideal gas constantT is the temperature (in kelvin)

So we deserve to see native this equation the if you take it a addressed amount that gas (n doesn"t change), and also you rise its temperature by heating it, either pressure or volume (or both) have to change. If you execute that heater in an fastened chamber, the push will increase. This would certainly lead you to the idea that warmth air is high pressure, yet that"s not fairly a true statement. What is true is the if you heat air in an enclosed space, friend will rise its pressure. On the other hand, if you heat the waiting in an open container v no lid, the pressure wont increase at all: the volume will increase.

Just due to the fact that air is compressed does not automatically make the "hot." the just means it has a high pressure. If you have experience through compressors, this could not it is in intuitive because, in practice, you discover that compressors warm the air fairly a little (especially if you"re filling air tanks for divers!). However, that is yes, really an concern of inefficiency. The piston based compressors take an early volume of air and also compress it really easily into a small volume. This is walking to either raise the pressure, the temperature, or both. In practice, it raises both. That"s no a desirable thing -- that wastes money to generate all the heat.

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Finally, come your model of collisions, if you have actually a hot gas and also a cold gas at the very same pressure, what girlfriend will find is the the hot gas will have fewer collisions, yet they will be much more energetic (higher velocity). The cold gas will have more collisions, but they will have less energy. They"re two different approaches to cause the exact same pressure.