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YumYum247

  • one year ago

yelp!!!

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  1. YumYum247
    • one year ago
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  2. YumYum247
    • one year ago
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    This is how i attempted to do the question..... Fn = nF1 (16.5Hz) Fn = 16.5Hz The fundamental frequency is 16.5Hz

  3. YumYum247
    • one year ago
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    can someone please give me a hint on how to solve for the speed of the wave...V = d/t How do i find time here?????????????? :(

  4. YumYum247
    • one year ago
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    |dw:1436754247641:dw|

  5. Astrophysics
    • one year ago
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    \[v = \lambda f\]

  6. Astrophysics
    • one year ago
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    What did you get for the first answer?

  7. YumYum247
    • one year ago
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    the fundamental frequency/natural frequency of the string is 16.5Hz

  8. Astrophysics
    • one year ago
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    But it's asking for the string

  9. Astrophysics
    • one year ago
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    \[\huge f_{freq} = 3 f_{string}\]

  10. Astrophysics
    • one year ago
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    Where your \[f_{freq} = 16.5 Hz\]

  11. YumYum247
    • one year ago
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    fundamental frequency is the lowest frequency that a system can produce to make a standing wave.

  12. YumYum247
    • one year ago
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    that would the natural frequency in the 3rd harmonic phase.

  13. YumYum247
    • one year ago
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    i did a question earlier related tho this, and the fundamental frequency of the wave was the very lowest that a wave produced in a fixed postion....like this |dw:1436755214463:dw|

  14. YumYum247
    • one year ago
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    that is the fundamental frequency of the wave....F = 30/.20 = 150Hz So the other two frequencies i had to figure out that make the standing waves were.... Fn = nF2 Fn = F2(150) = 300Hz Fn = nF3 Fn = F3(150) = 450Hz

  15. YumYum247
    • one year ago
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    |dw:1436755541130:dw|

  16. YumYum247
    • one year ago
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    |dw:1436755603442:dw|

  17. YumYum247
    • one year ago
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    |dw:1436755633977:dw|

  18. YumYum247
    • one year ago
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    but how do i find the time of wavelength?????????????:/

  19. YumYum247
    • one year ago
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    @mathmate

  20. YumYum247
    • one year ago
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    @pooja195

  21. IrishBoy123
    • one year ago
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    *can someone please give me a hint on how to solve for the speed of the wave* its a standing wave and its wave form is not actually visibly *travelling* but it still has "velocity" \( v = \frac{2 \ L \ f_n}{n} \) so velocity \(v\) and freq \(f_3\) for the 3rd harmonic are related as follows: \( v = \frac{2 \ L \ f_3}{3} \) or \( f_3 = \frac{3v}{2L} \)

  22. YumYum247
    • one year ago
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    Thank you Irishman!!! :)

  23. YumYum247
    • one year ago
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    and is my fundamental frequency correct?????????????????? @IrishBoy123

  24. IrishBoy123
    • one year ago
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    this is a long old thread so let me step through it as i see it and you judge if this makes sense to you: first there is resonance with the 16.5Hz source so we can say: |dw:1436805378856:dw| v is fixed, it is a consequence if the tension in and density of the string. so the "fundamental harmonic will look like this: |dw:1436805640680:dw| if this makes sense, we can do the last bit and look again at that equation i posted as i think it is important to note that it is totally derivable and not something of a lack box. this fits nicely with part (iii) of the question so i hope this is all going according to plan.....

  25. IrishBoy123
    • one year ago
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    forgive "lack box" [= "black box"] and myriad other typos....

  26. IrishBoy123
    • one year ago
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    in terms of what can be a resonant frequency, here is the beginning of the possible standing wave patterns: |dw:1436806502148:dw| IOW: \(\lambda_n = \frac{2 L}{n}\) and \(v = f . \lambda\) which gives us the formula i quoted previously, \(f_n = \frac{v}{\lambda} = \frac{n . v}{2L}\) ergo, resonant frequencies go in integer multiples of \(\frac{ v}{2L}\) which here is \(\frac{66}{2*6} = 5.5Hz\). and \(\frac{28.5}{5.5} = ???\) does that make sense to you? do you agree?

  27. YumYum247
    • one year ago
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    |dw:1436844986642:dw|

  28. YumYum247
    • one year ago
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    |dw:1436845232173:dw|

  29. YumYum247
    • one year ago
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    f1 = 5.5Hz and V = 66m/sec

  30. YumYum247
    • one year ago
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    The next question asks me to find whether or not the new frequency of 28.5Hz would make a standing wave on the spring??????And this is how i did it.......|dw:1436847792123:dw|

  31. YumYum247
    • one year ago
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    |dw:1436847968394:dw|

  32. YumYum247
    • one year ago
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    i think in order for the new frequency to produce a complete standing wave, it has to be twice as big as the fundamental frequency....in this case 33Hz to make the next standing wave on the string......am i right???????O-o

  33. YumYum247
    • one year ago
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    @IrishBoy123 @Astrophysics the question asks me to find the minimum length of air in a column required for resonate??????This is how i did it...please check my work :)

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  34. YumYum247
    • one year ago
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    |dw:1436850740578:dw|

  35. YumYum247
    • one year ago
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    |dw:1436851048790:dw|

  36. YumYum247
    • one year ago
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    is that the minimum length of air/ fundamental length of air????????

  37. YumYum247
    • one year ago
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    @Michele_Laino Can you please check my work??????

  38. YumYum247
    • one year ago
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    the question asks me to find the fundamental frequency....i've done it up there but no one bothered to check my work, could you please give me a hand here???

  39. Michele_Laino
    • one year ago
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    I'm very sorry, I don't know your answer, since in my physics courses I have not studied acoustics

  40. YumYum247
    • one year ago
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    Aawwnnnn!!! :(

  41. YumYum247
    • one year ago
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    @Elsa213

  42. Elsa213
    • one year ago
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    @dan815

  43. Elsa213
    • one year ago
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    @sleepyhead314

  44. Elsa213
    • one year ago
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    @teagirl7630

  45. anonymous
    • one year ago
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    @Elsa213 I'm not good at physics...sorry :/

  46. YumYum247
    • one year ago
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    aight so this is my fundamental frequency.|dw:1436887286398:dw|