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industry86
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--It is found that a 6.00m segment of a long string contains four complete waves and has a mass of 180g. The string is vibrating sinusoidally with a frequency of 50.0hz and a peak-to-valley distance of 15.0cm. (a) Write the function that describes this wave traveling in the positive x direction. (b) Determine the power being supplied to the string.--
Ok, I determined that w=2*pi*50hz=314 rad/s. k= (2*pi)/wave length=4.19rad/m (assuming that the 6m long segment with 4 equal length waves would give me a 1.5m wave length)
so i can answer (a), although having the A=6.00m is starting to bug me since the string is actually a lot longer that the segment experiencing the waves.
(b), is killin me though. I figure all i have to use is the P=1/2*u*w^2*A^2*v bit, but i can't seem to figure out v.
v=wave length*freq.
v=w/k
v=sqrt(period/u)
but if I use what I have determined previously, the first two equations come up with teh same answer, but the third one doesn't. the first 2 are 75m/s, the third is something like .81m/s. This makes me think that either my period, which I determined is .02s, is wrong, or something else is fundamentally wrong. And am I even using the right equation for the power?
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Um, since I don't know how to delete this post, I'll just correct myself here.
v=wavelength*freq
v=w/k
v=sqrt(TENSION!...not period/u)
please ignore this now
Ok, I determined that w=2*pi*50hz=314 rad/s. k= (2*pi)/wave length=4.19rad/m (assuming that the 6m long segment with 4 equal length waves would give me a 1.5m wave length)
so i can answer (a), although having the A=6.00m is starting to bug me since the string is actually a lot longer that the segment experiencing the waves.
(b), is killin me though. I figure all i have to use is the P=1/2*u*w^2*A^2*v bit, but i can't seem to figure out v.
v=wave length*freq.
v=w/k
v=sqrt(period/u)
but if I use what I have determined previously, the first two equations come up with teh same answer, but the third one doesn't. the first 2 are 75m/s, the third is something like .81m/s. This makes me think that either my period, which I determined is .02s, is wrong, or something else is fundamentally wrong. And am I even using the right equation for the power?
---------------------------------------------
Um, since I don't know how to delete this post, I'll just correct myself here.
v=wavelength*freq
v=w/k
v=sqrt(TENSION!...not period/u)
please ignore this now
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