Understanding Period and Frequency in Waves and Pressure Changes

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Seiya
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Say if i have an equation:

x = cos pi/2 (x-330t)

someone told me that 330/4 is the period. I just want to know how come... what's the 330 represent exactly? i tought it was w (angular frequency) which would mean w/2(pi) = f ... and 1/f = T but i don't get the same results as what he said (330/4) = T...


I'm very confused about this and I've got a test tomorrow... if someone could explain it to me Id very much appreciate it. Thank you
 
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The general form for a wave is

y(t) = cos ([itex]\omega[/itex]t + [itex]\theta[/itex]) where [itex]\omega[/itex] is the angular frequency (= 2[itex]\pi[/itex]f) and [itex]\theta[/itex] is the phase angle, which is based on the initial condition. The period T = 1/f, and if the wave speed = c, then c = f[itex]\lambda[/itex], where [itex]\lambda[/itex] is the wavelength.

Another way to write this expression is

y(x,t) = A sin ([itex]\omega[/itex]t - kx), where k is the wave number, and kx is the phase lag. If kx was preceded by +, the it would represent a phase lead.
 
Oh god how embarassing, all this time i was confused about this topic because of a simple MATH error... i canceled out something i should not have canceled out!

Oh my god *blushes* :(

Thanks for the help... i still can't believe this lol... =\
 
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