socialgain
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http://filestore.aqa.org.uk/subjects...W-QP-JAN10.PDF

Could anyone explain question 4 to me? I don't have a clue what to do
For the first part, how am I meant to draw 'one loop' as it states on the mark scheme, does this mean one wavelength?
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victoria98
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Fundamental frequency is the lowest frequency in a harmonic series where a stationary wave will form. So by 'one loop' they mean half a wavelength - two nodes and one antinode. Like this.
Then if 0.64m is half a wavelength, the wavelength is 1.28m.
Use v(c) = f λ to find the speed (they give you the frequency and you just worked out the wavelength)
For the next part draw a wave with four nodes (0.64m/0.16=4)
For the next part you can use the same wave speed equation or you could multiply the fundamental frequency, provided at the very beginning, by 4.
I hope that makes some sense.
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KINGYusuf
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Fundamental frequency is 1/2wavelength

Calculating the wavelength of the fundamental mode of vibration:

1/2Wavelength = 0.64m
Therefore wavelength = 1.28m

Speed:
V = fwavelength(lamda)
Therefore V = 108 x 1.28 = 138.24m/s

Btw i've only just started learning this topic might not be 100% correct but cba to go on sorry LOL
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socialgain
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(Original post by victoria98)
Fundamental frequency is the lowest frequency in a harmonic series where a stationary wave will form. So by 'one loop' they mean half a wavelength - two nodes and one antinode. Like this.
Then if 0.64m is half a wavelength, the wavelength is 1.28m.
Use v(c) = f λ to find the speed (they give you the frequency and you just worked out the wavelength)
For the next part draw a wave with four nodes (0.64m/0.16=4)
For the next part you can use the same wave speed equation or you could multiply the fundamental frequency, provided at the very beginning, by 4.
I hope that makes some sense.
Thanks for the help, teacher seemed to skip over this topic completely
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