Braingle: 'Joe Thunder' Brain Teaser

Joe Thunder

Science brain teasers require understanding of the physical or biological world and the laws that govern it.

Puzzle ID:	#11245
Fun:	(3.16)
Difficulty:	(2.73)
Category:	Science
Submitted By:	od-1
Corrected By:	4demo

As his name would suggest, Joe was not a meek, quiet fellow. In fact he had such difficulty keeping quiet, both his local and university library banned him. His roommate, being a music major and a sound engineer, said he could solve his problem, but Joe would need to trust him. He gave Joe his 75-watt ghetto blaster, a CD, fake mustache, and a long blond wig. Joe, who is sceptical but intrigued, decided to give it a shot. Joe, disguised as one of the professors, entered the university library. He placed the CD player on the table in front of him; loaded the CD; cranked the volume full and braced himself as he turned it on. Surprisingly there was only a very very faint sshh. Joe then realized that he couldn't hear anything at all. He spoke normally, and then yelled, but no one reacted. Awesome, he thought as he began flailing his arms around and shouting as loud as he could. Unfortunately, the librarian, seeing him moving but hearing nothing, assumed he was choking and performed the Heimlich maneuver on him, knocking his wig off, causing the librarian to perform the hind kick maneuver right out the door. Poor Joe.
But what had his roommate done? What was on that mysterious CD that made everything quiet?

Hint

Think sound and what people can and can't hear.
Hide

Show Answer

What Next?

See another brain teaser just like this one...

Or, just get a random brain teaser

If you become a registered user you can vote on this brain teaser, keep track of
which ones you have seen, and even make your own.

Comments

(user deleted) Mar 26, 2003	Hehe... hind kick maneuver... that's funny :-)
iloveh20melon Mar 27, 2003	cool teaser
griphook Mar 30, 2003	Hear Ye! Hear Ye ! a good informative teaser. More
electronjohn Apr 02, 2003	Sounds good to me.
Codammanus May 14, 2003	I like this one. In fact, I was going to do a teaser with a similar concept, but I won't know. It was done nicely here!
ousgg Jun 06, 2003	Erm...one problem with this teaser. Mr. Thunder would have to have a very, very good CD player in order for this to work. Manufacturers tend to build stereo equipment that only responds to the human aural response range (in order to filter out unwanted electrical impulses and suchlike) - hence the low-frequency sound on the CD would not make it past all but the very best speakers.
nshachafn Oct 10, 2004	i don't get it....
Z2-d2 Dec 09, 2004	rad I love your teasers
Kollonel_Rabbit Jan 15, 2005	i figured out the waves canceling part but not the specifics
silly_goose Jun 25, 2005	Wow! I totally did NOT get that one, but I learned a lot! Awesome!
marching_xc Jul 06, 2005	How interesting. I like these science teasers; I learn neat facts from them!
puppygirl1213 Aug 25, 2005	I did not know that, very cool
Rhettfairy Oct 15, 2005	Cool little fact, but very poorly written to tell the truth. I had a hard time deciphering the riddle due to the lack of proper punctuation and such. More of a trivia question than a riddle or puzzle really, as it took actual knowledge of the technology rather than problem-solving skills to figure it out.
bookworm91 Dec 04, 2005	cool teaser. actually rhettfairy, this is not truley a riddle. its a science riddle which is like trivia only....science although you probably did have to be a science whiz to know that one! that was very interseting and i learned something new.
choptlivva Dec 22, 2005	Wow..... I found this one to be absolutely fascinating!!! I had no idea there was "sound cancelling" technology!! Makes me wonder if the "principle" demonstrated here explains why a person with a mild to moderate hearing loss has more trouble understanding speech when there is background noise. I know that most consonant sounds in human speech are in the higher frequency range. Assuming that the background noise is of a lower frequency, but still audible.... would the background noise actually cancel out the higher pitched sounds, and thus make it difficult for one to understand conversation? Any scientists out there that know the answer to this?
Vigo95 Apr 14, 2006	i knew this one . some guy let me use his bose headphones on the plane .
Vudluxi May 28, 2006	Excellent, I hadn't heard of that before (no pun intended). I can't believe someone complaining about the punctuation. Maybe they had PERIOD pains or need to undergo COLONic irrigation .
_numpty_ Nov 20, 2006	Bose use a different technology... look up Noise cancelling headphone in Wikipedia (link not allowed here since it has >50 letters)
brucemcdon Apr 02, 2007	Here is a link to the Wikipedia article about how noise cancellation actually works. http://tinyurl.com/2ebor6 Joe's boombox would have to be very advanced indeed.
ankurtg Jul 20, 2007	This is utterly nonsensical. The phenomenon demonstrated here is as fictitious as Joe Thunder. Active Noise Cancellation doesn't work by playing random infrasounds as said here. It produces sound patterns identical to ambient noise, inverted. So the two (Noise and Anti-Noise) cancel out in the ear. The idea of an inaudible sound "drowning" other sounds simply because it's more intense (not LOUDer, loudness concerns audible sounds) is against the Principle of Superposition.
TravisG Feb 06, 2011	This is not how sound cancellation works. The author has confused masking with sound cancellation. Masking works by playing a sound loud enough to render another sound inaudible. Sound cancellation works by creating another sound with 180 degree phase shift to reduce the amplitude of the first sound. An inaudible sound cannot be "louder" than an audible sound and an inaudible sound cannot mask an audible sound.
babyjuice Jun 17, 2012	That is AWESOME!!! I don't care what all those comments said, it's still one of the coolest things I've ever heard of. I wish there was, like, a YouTube video that recorded that sound, then I would play it and talk. AWESOME!!
babyjuice Jun 17, 2012	That is AWESOME!!! I don't care what all those comments said, it's still one of the coolest things I've ever heard of. I wish there was, like, a YouTube video that recorded that sound, then I would play it and talk. AWESOME!!