YumYum247 one year ago 3

1. YumYum247

i think if the length of the chime gets shorter, the frequency will also shorten proportionally... am i right!!!

2. YumYum247

@IrishBoy123

3. YumYum247

last one!!!! :"D

4. YumYum247

never mind i may be wrong!!!

5. YumYum247

cuz the length has nothing to do with the frequency of the sound.

6. YumYum247

it's just a medium that the sound is travelling through, it could be longer or shorter!!!

7. IrishBoy123

i think we agreed that $$f_n = \frac{n.v}{2L}$$ because v = const, for any harmonic we know that $$f \propto \frac{1}{L}$$ so if you shorten the chime, the res frequency must increase.

8. YumYum247

but praticaly it dosn't make sense tho!!!

9. YumYum247

i understand that the speed of the wave is constant, but if you decrease the size/length of the medium, should the frequency stay the same????

10. YumYum247

how is frequency directly dependent on the length of the air column????

11. YumYum247

it's like saying if a train is going at a 50km/h speed on a 100km track, if you shorten the track, the train will still be going at the same speed.

12. YumYum247

how does the intensity of the energy (f) changes as the length increases or decreases?!?!?!?!

13. IrishBoy123

nothing makes sense if you think about it hard enough. but familiarity with an idea brings a complacent sense of knowing or understanding in this specific case, pluck a guitar string, then the push on a fret and pluck it again. pitch / frequency increases, length of string has decreased. so we do some mths and it all seems obvious! it doesn't make any sense, of course but we get used to it and we think it is obvious!! and we have a nice little equation. and some myriad other explanations about the kinetic energy of molecules which we cannot actually see. blow across the top of a (an unopened) 125ml coke bottle. blow across the top of a 2L bottle of coke. pitch decreases.

14. IrishBoy123

and the wave has no actual speed because it is a standing wave, it is going nowhere. so we are talking about the 2 opposing waves that meet and create the standing wave. they have speeds that cancel out to create the stationary wave. it's all very artificial, yet incredibly beautiful at the same time. hope you're not bothered by this stuff. you seem to be very serious about your study and that should take you a long long way.

15. IrishBoy123

crumbs! blow across the top of a (an **opened**) 125ml coke bottle.

16. YumYum247

i understand that only energy in the form of waves trvel through the medium, the medium itself isn't going anywhere, similar to the wave people make in the stadium..

17. anonymous

the ends of the chime put boundary conditions on the wavelengths of waves that it can support; shorter maximum wavelength => higher fundamental frequency

18. anonymous

well, boundary conditions on the waves that it can support, so this limits the maximum wavelength

19. YumYum247

can i use flute as an example??????? because everytime you blow into the flute with all the holes closed, the noise comming out of the flute will have a less pitch as compare to when a hole is open because the lenght of the air column is maximum and therefore............ some please finish the sentense

20. YumYum247

therefore it'll play a lower pitch?

21. YumYum247

as you open and close the holes of the flute, the length of the air column shorten and the frequency of the sound increase, causing the pitch of the sound to increase?

22. anonymous

if you close all the holes, you change the boundary conditions of the waves so it can support a maximally long wavelength and thus the fundamental frequency is going to be lower (i.e. the flute has lower pitch)

23. YumYum247

ok so the longer the colum the less frequency and the shorter the column the higher the frequency!!!! right????

24. anonymous

the holes being open says that the pressure must be 'fixed' there, so opening holes closer to the mouth piece results in shorter wavelengths fitting the boundary conditions and a higher fundamental frequency

25. YumYum247

because as you increase or decrease the length, your also manipulating the boundary conditions, meaning the shorter the length the shorter the fundamental frequency right????

26. YumYum247

did i say the last two comments correct???