Helium changing voice...?

Cecil's Columns/Staff Reports
1

Here’s a question I had regarding a statement made in the thread of helium changing your voice…

http://www.straightdope.com/mailbag/mheliumsqueak.html

“Helium is significantly less dense than air. As a result, the speed of sound is much higher in helium.”

Now my years of physics this sound counter intiutitve, as speed travels FASTER in denser objects, not in LESS dense objects.
Bang a metal pole sound zips down it faster than through air.
If you take an extreme case of a infintesimally low density, you get a slower speed (think vacuum of space, speed of sound = 0 )

Anyways, thanks :slight_smile:

2

yeah, I too thought it was a bit contradictory.

I remember being cautioned not to suck helium out of balloons becuase it tightened your throat and constricted your air passages (in turn raising your voice). I don’t knlow if this is true (helium is a noble gas, no? why should it affect a throat?).

3

Quite often, there are previous threads about StaffReports, Cecil’s columns, etc. If you’re new, you might not think to search for them.

Here’s One which addresses your concern. And, hopefully, explains it.

4

Yah saw the search after I posted, my apologies… since I had to register just to search, I figured I might as well post after I registered, that and I can’t edit/delete my post.

5

Nonetheless, sfsuphysics, welcome aboard, glad to have you with us, and hope that you’ll engage in more posting.