Can a 28.5Hz Frequency Cause a Standing Wave in a 6m Long String?

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A 6.0m long string vibrating with three loops at a source frequency of 16.5Hz has a fundamental frequency of 5.5Hz and a wave speed of 66m/s. The wavelength is calculated to be 4m, derived from the length of the string divided by the number of loops. A frequency of 28.5Hz does not produce a standing wave in the string, as it is not a multiple of the fundamental frequency. There is a debate about the calculation of the fundamental frequency, with some suggesting it should be derived from the speed divided by wavelength instead. The thread is now closed due to the original poster's inactivity.
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1. A string that is 6.0m long is vibrating with three loops in it. The frequency of the source is 16.5Hz.

What is the fundamental frequency of the string?

What is the speed of the waves in the string?

Explain whether or not a source of frequency of 28.5Hz causes a standing wave in the string.
3. Info: 6m long string. Source frequency is 16.5Hz. There are 3 loops.
Find wavelength:
6m/3=2m
Each loop is 2m.
1 loop is half a wavelength.
λ=2*2
λ=4m
Since the frequency is 16.5Hz with three loops, to find fundamental frequency you just divide by three.
16.5/3=5.5Hz
The fundamental frequency is 5.5Hz
Find speed with velocity equation: v=ƒ*λ
v=16.5*4
v=66m/s
The speed of the waves in the string is 66m/s

A source frequency of 28.5Hz would not cause a standing wave in the string because it is not a multiple of the fundamental frequency 5.5Hz.
28.5Hz/5.5Hz=5.182Hz
 
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What's your question? Or do you just want an approval stamp from PF ?
(By the way: I can't find anything wrong with what you write...
except: Hz/Hz is not Hz. The quotiënt is a simple number
:smile:)
 
I think your fundamental freq is wrong, you should be dividing speed by wavelength, not number of loops. Doing this returns fundamental freq as 4.125, which is a multiple of the initial freq (16.5).
 
Tarragon said:
I think your fundamental freq is wrong, you should be dividing speed by wavelength, not number of loops. Doing this returns fundamental freq as 4.125, which is a multiple of the initial freq (16.5).
This thread is from August 2014. The Original Poster has not logged in since August 27th, 2014. It is therefore highly unlikely that you will get a response from them.

Because of its age and lack of evidence that thee OP has any interest in it, I am closing this thread to further posts.
 
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