What is the formula for calculating wave speed through a gas?

AI Thread Summary
The discussion focuses on calculating wave speed through a gas using the formula v = frequency × wavelength. An initial attempt to find the wavelength resulted in a calculation of 0.06 meters, leading to a wave speed of 719.76 m/s. However, this calculation was incorrect due to not accounting for the changes in length when a section is pulled out by 0.03 m. The correct approach involves recognizing that the length increases in both the top and bottom parts of the system. This insight clarifies the misunderstanding and aids in accurately determining wave speed.
road_runner
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I tried finding lambda:
.03 = wavelength/2 --> wavelength = (.03)(2) = .06

Then plugging that into the equation
v = (frequency)(wavelength) --> v = (11996)(.06) = 719.76

But that didn't work.
 
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Hello road_runner,

Welcome to Physics Forums!
road_runner said:
I tried finding lambda:
.03 = wavelength/2 --> wavelength = (.03)(2) = .06

[...]

But that didn't work.
Reevaluate the comparative length of the path LYM, when the section is pulled out by 0.03 m. The LYM section can be broken up into two parts: the length of the top part and the length of the bottom part.

When the sliding section is pulled out, the LYM distance increases by 0.03 m due to the increase in length of the top part, and yet another 0.03 m care of the bottom part. :wink:
 
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Ahhh ok! Thanks a million! Never even considered that the length changes in both parts...
 
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