Longitudinal vs. Transverse Wave

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Can someone just confirm this for me?

So if I pluck a string attached to points on both ends like on a guitar, its motion is described as a transverse wave, right? But what about the sound emanating from the string's motion-- isn't the sound a longitudinal wave? So is it described as both?

What about the waves produced in open and closed pipes? Longitudinal as well? Thanks!

 

[dudewheresmymd]

You got it. A string that resonates and has nodes at both ends (such as a guitar string) produces a standing wave, but the vibrations with the air molecules create compressions and refractions that lead to a longitudinal sound wave as seen below:

An organ would be a "closed at one end pipe" that creates sound waves that are longitudinal. These waves are only created when the air is compressed and refracted in a longitudinal fashion.

Helpful link:
http://www.physicsclassroom.com/mmedia/waves/gsl.cfm

 

[clothcut]

You got it. A string that resonates and has nodes at both ends (such as a guitar string) produces a standing wave, but the vibrations with the air molecules create compressions and refractions that lead to a longitudinal sound wave as seen below:

An organ would be a "closed at one end pipe" that creates sound waves that are longitudinal. These waves are only created when the air is compressed and refracted in a longitudinal fashion.

Helpful link:
http://www.physicsclassroom.com/mmedia/waves/gsl.cfm

Cool, thanks! I was reading today about compressions and rarefactions of air... would the max amplitude of a longitudinal sound wave correspond with the area of air being momentarily compressed?

 

[dudewheresmymd]

Cool, thanks! I was reading today about compressions and rarefactions of air... would the max amplitude of a longitudinal sound wave correspond with the area of air being momentarily compressed?

More or less, the amplitude of a sound wave is the difference in pressure between the undisturbed air and the max pressure caused by the wave. Most likely MCAT won't test you on this...but be aware of amplitude of transverse waves (max. displacement from equilibrium).