Calculating Properties of a Transverse Wave on a Rope

[lordrrr]

Homework Statement

A transverse wave on a rope is given by the following equation.
y(x, t) = ( 0.710 cm ) cos pi [(0.400 cm^-1)x + (500 s^-1)t]

From this, find the amplitude, period, frequency, wavelength and the speed of propogation.

Homework Equations

Well, I know that v=f*lambda. I also know the general equation for sinusodal models in the -x direction:

y(x,t)= A*cos2pi[(x/lamda)+(t/period)]

(I choose to use this particular equation because it ties in with the one given to me)

The Attempt at a Solution

This problem is driving me nuts. I should be able to just take out the units that it aligns with and get that for the answer, right? I took out the 0.71, so I found the amplitude. I found the frequency by dividing 500 by 2. I found the period by dividing 1/250. But I can't for the life of me find the wavelength or the speed of propogation, can anyone please help? Thanks very much!

 

[lordrrr]

Can anyone please help? I'm so lost.

 

[robvienn]

The form y(x,t) = A cos (kx-wt) is more appropriate here...k is equal to 2PI/lambda and
w = vk. So your amplitude is given, period and frequency can be derived from the value given for angular velocity (w), wavelength derives from the value for k...and your speed of propagation is found using angular velocity (w) and wave number (k). Good Luck!