# Smoke goes out the window...

**URL:** <https://boards.straightdope.com/t/smoke-goes-out-the-window/499674>\
**Category:** Factual Questions\
**Created:** [June 13, 2009, 5:33pm UTC](https://boards.straightdope.com/t/smoke-goes-out-the-window/499674 "2009-06-13T17:33:22Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Serenata67](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/serenata67/32/10646_2.png) [@Serenata67](https://boards.straightdope.com/u/Serenata67)\
**Post date:** [June 13, 2009, 5:33pm UTC](https://boards.straightdope.com/t/smoke-goes-out-the-window/499674/1 "2009-06-13T17:33:22Z")

</div>

This is something I’ve been wondering about since 8th grade, and I think I’ve finally found the proper forum to finally get some answers. When smoking a cigarette in the car, the blue-gray whisps of smoke almost always seem to be sucked right out the window. It seems to be especially true the faster you’re driving. How is it that the smoke gets sucked out?

---

<div class="post-metadata">

**Author:** ![Finagle](https://avatars.discourse-cdn.com/v4/letter/f/b19c9b/32.png) [@Finagle](https://boards.straightdope.com/u/Finagle)\
**Post date:** [June 13, 2009, 5:59pm UTC](https://boards.straightdope.com/t/smoke-goes-out-the-window/499674/2 "2009-06-13T17:59:07Z")

</div>

Probably an instance of [Bernoulli’s Principle](http://en.wikipedia.org/wiki/Bernoulli's_principle). The air is moving by the windows at a high speed causing a low pressure area that sucks the air out of the car. Air is probably entering the car through the vents at the same time.

---

<div class="post-metadata">

**Author:** ![Serenata67](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/serenata67/32/10646_2.png) [@Serenata67](https://boards.straightdope.com/u/Serenata67)\
**Post date:** [June 13, 2009, 7:41pm UTC](https://boards.straightdope.com/t/smoke-goes-out-the-window/499674/3 "2009-06-13T19:41:11Z")

</div>

Thank you!