system
Given the following post, respond as if you're commenting on Reddit:
human
Car-window air-pressure pulsing??

Have you ever been driving down the highway and when you role down one window (half-way or just the right amount) the air in the cabin starts pulsing? It makes a really loud noise almost as if a sub-woofer was fluttering at high speeds, but when you adjust the window a few inches it goes away?  What's up with that?
gpt
What is happening is a dynamic air pressure equilibrium. The motion of the car forces air into cabin through the half-open window, increasing the inside air pressure. Eventually the pressure differential is great enough to great enough for the air to rush back out. This process repeats causing the sub-woofer-like pulsating. Blowing air over the top of a bottle creates exactly the same phenomena, albeit at a more pleasantly musical pitch. To resolve the issue you can fully open the window (allowing air in through the top and out through the bottom, or vice versa) or crack the passenger side window (to allow air in one side and out the other). Hope that all made sense!