How Do You Calculate Wave Parameters for a Transverse Sinusoidal Wave?

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Homework Statement


A transverse sinusoidal wave is moving along a string in the positive direction of an x-axis with a speed of 80 m/s. At t = 0, the string particle at x = 0 has a transverse displacement of 4.2 cm from its equilibrium position and is not moving. The maximum transverse speed of the string particle at x = 0 is 18 m/s.
It asks to solve for f,λ,[itex]y_{m}[/itex],k,ω, and [itex]\phi[/itex] in the wave formula


Homework Equations



y(x, t) = [itex]y_{m}[/itex] sin(kx ± ωt + [itex]\phi[/itex])


The Attempt at a Solution


Since it says at t and x = 0 the displacement is 4.2cm and stopped moving i assumed that meant that it had reached its max displacement. I then used [itex]u_m=ωy_m[/itex]
for the max transverse speed and solved for ω, which i put into the formula
f=[itex]\frac{ω}{2\pi}[/itex] which gave me [itex]0.00367s^-1[/itex], and solving for wavelength using [itex]λ=\frac{v}{f}[/itex] gave me 21827m which doesn't seem right, I'm pretty sure I'm doing something wrong, any help would be appreciated.

thanks

Oh and btw i converted all the cm to m before calculating.
 
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You wrote,

u_m=ωy_m (why can't I copy and paste your formulas intact? Oh well)

Did you mix units, the displacement was given in cm and the velocity in m/s ? We want everything in cm or m.
 
Yes i converted 4.2cm to 0.042m, then divided 18m/s by 0.042m to get a very large ω value of 428.6
 
Ok, i calculated again and i think i switched the denominator with the numerator in something. Seems to be more reasonable now.
Thanks