# How can the speed of light be 38 MPH??!!!???

**URL:** <https://boards.straightdope.com/t/how-can-the-speed-of-light-be-38-mph/5392>\
**Category:** Factual Questions\
**Created:** [December 14, 1999, 11:27pm UTC](https://boards.straightdope.com/t/how-can-the-speed-of-light-be-38-mph/5392 "1999-12-14T23:27:00Z")\
**Posts on this page:** 1\
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**Author:** ![RealityChuck](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/realitychuck/32/195_2.png) [@RealityChuck](https://boards.straightdope.com/u/RealityChuck)\
**Post date:** [December 15, 1999, 4:09pm UTC](https://boards.straightdope.com/t/how-can-the-speed-of-light-be-38-mph/5392/16 "1999-12-15T16:09:00Z")

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You see “slowed down light beams” all the time. It’s called “refraction.”

In other words, light bends in a lens because it slows down as it passes through glass. The difference in speed isn’t much, but it’s enough to produce noticeable effects.

## I’d guess that if you slowed down light to 38 MPH, the refraction will be even more noticeable.

“East is east and west is west and if you take cranberries and stew them like applesauce they taste much more like prunes than rhubarb does.” – Marx

Read “Sundials” in the new issue of Aboriginal Science Fiction. [www.sff.net/people/rothman](http://www.sff.net/people/rothman)

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