# Ear pressure in car **URL:** \ **Category:** Factual Questions\ **Created:** [June 30, 2013, 2:29am UTC](https://boards.straightdope.com/t/ear-pressure-in-car/662238 "2013-06-30T02:29:17Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Thus\_Spoke\_Me](https://avatars.discourse-cdn.com/v4/letter/t/e9a140/32.png) [@Thus\_Spoke\_Me](https://boards.straightdope.com/u/Thus_Spoke_Me)\ **Post date:** [June 30, 2013, 2:29am UTC](https://boards.straightdope.com/t/ear-pressure-in-car/662238/1 "2013-06-30T02:29:17Z")
So, whenever I roll down a window in my car I almost immediately feel a weird pressure in my ears, and it goes away if I open up the parallel window. What causes this? I assume that is has something to do with the variant air pressure, but it would be nice to have a more detailed answer. ---
**Author:** ![nion](https://avatars.discourse-cdn.com/v4/letter/n/c5a1d2/32.png) [@nion](https://boards.straightdope.com/u/nion)\ **Post date:** [June 30, 2013, 6:25am UTC](https://boards.straightdope.com/t/ear-pressure-in-car/662238/2 "2013-06-30T06:25:23Z")
Just a guess, but air pressure could be building from air being forced into the car, but not having a ready exit. Both windows open would allow both entry and exit for the air, lowering the effective air pressure. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [June 30, 2013, 12:07pm UTC](https://boards.straightdope.com/t/ear-pressure-in-car/662238/3 "2013-06-30T12:07:49Z")
I believe it’s because with one window open, your car is acting as a [Helmholtz resonator](http://en.wikipedia.org/wiki/Helmholtz_resonance). This is what causes the low pitch sound you hear when you blow across the top of a bottle. Your car is much larger, so the frequency is very low, below the range of your hearing. Maybe look at the Wikipedia page on [Infrasound](http://en.wikipedia.org/wiki/Infrasonic). From there > [@](#): > > 20 Hz is considered the normal low-frequency limit of human hearing. When pure sine waves are reproduced under ideal conditions and at very high volume, a human listener will be able to identify tones as low as 12 Hz.[30] Below 10 Hz it is possible to perceive the single cycles of the sound, along with a sensation of pressure at the eardrums. ---
**Author:** ![drewtwo99](https://avatars.discourse-cdn.com/v4/letter/d/d07c76/32.png) [@drewtwo99](https://boards.straightdope.com/u/drewtwo99)\ **Post date:** [June 30, 2013, 3:56pm UTC](https://boards.straightdope.com/t/ear-pressure-in-car/662238/4 "2013-06-30T15:56:55Z")
I can verify this effect, but for me only if a roll down one of the back windows and none of the front. I hear a very distinctive “womp womp womp” and estimating the frequency would put it somewhere at around 10Hz I’d imagine. This occurs inside my ears and is very disorienting and unpleasant. ---
**Author:** ![Blind\_Guardian](https://avatars.discourse-cdn.com/v4/letter/b/df705f/32.png) [@Blind\_Guardian](https://boards.straightdope.com/u/Blind_Guardian)\ **Post date:** [July 1, 2013, 12:32am UTC](https://boards.straightdope.com/t/ear-pressure-in-car/662238/5 "2013-07-01T00:32:10Z")
I have precisely the same experience that **drewtoo99** does when I have a back window open, but not one of the front ones. If I just have a front window open, I don’t experience the phenomenon. It’s distinctly uncomfortable, and I’ve wondered what it is about the design of my car that makes this occur. I’ve thought about starting a thread on this very subject, but I’d never gotten around to it. Thanks for the links, **Zenbeam** , that was interesting and informative.