system
Given the following post, respond as if you're commenting on Reddit:
human
When filling something with an air compressor, does the rate at which it fills decrease as the pressure increases?

A month or so ago I was filling up the tire on one of our cars and it seemed to be taking forever.

This led me to ponder the rate at which air was coming out of the pump. I couldn't find any numbers on it, so I'm turning to you askscience.

Here is my logic: Air compressors (not really sure how they work, to be honest) through some witchcraft and wizardy create pressure inside the tank and then push air into an object through a nozzle. The air flow seems like it should have a rate, or the rate at which the object is increasing in volume (Kilograms per second or something perhaps?). However, as the pressure in the object increases, the object pressure gets closer to the level of the tank, so the change in pressure is decreasing, making it harder for air to be pumped into the object being inflated.

The question: Is my logic true?

edit: Liters/second -> kilograms/second (thanks unhedged)
gpt
Yep, you're quite correct. Once the pressure in the object reaches the same as the maximum pump pressure, there would be no flow at all. If you then gave the tire a good squeeze, air would flow back through the compressor until the pressure equalised again.