oscillations in a closed pipe

[nina]

Why cant closed pipes produce even numbered harmonics? I have been given an explaination, but it isnt very detailed. I'm doing A2 (or just A level) physics, so an explaination suitable for this level would be greatly appreciated!
Thanks.

[himanshu121]

What explanation have been given to you so far

[nina]

Just that the 1st overtone has a frequency of 3 times the fundamental frequency, therefore the second harmonic is missing.

Is that all I need to know? It doesnt seem much of an explaination to give in an exam.

Thanks for your help...

[himanshu121]

yup it not enough Can u calulate the wavelength in terms of L

[nina]

Yes, I can calculate the wavelength from L. But why is there no second harmonic in a closed pipe?

[himanshu121]

Coz for Even harmonics u need a arrangement like this
2f, 4f which is clearly not possible

And u never get L = even integer * Wavelength

[himanshu121]

http://www.phys.unsw.edu.au/music/pipes.html

[nina]

Thanks! I will look at that more closely. thanks for the link too.[:)]

[himanshu121]

basically it is due to the fact that there is pressure antinode and node at closed and open ends

[nina]

actually, it makes sense now.
thank you so much. i may just get a good grade in my exam now...
[:)]

[himanshu121]

Goodluck for exams[:))]