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Homework Statement
In a demonstration, a 0.45 kg horizontal rope is fi xed in place at its two ends (x = 0 and x = 5.0 m) and made to oscillate up and down in the fundamental mode, at frequency 4.0 Hz. At t = 0, the point at x = 2.5 m has zero displacement and is moving upward in the positive direction of a y-axis with a transverse velocity of 5.0 m/s.
(a) What is the amplitude of the motion of that point?
(b) What is the wave speed in the rope?
(c) What is the tension in the rope?
Homework Equations
w=2*pi*f
k=2*pi*λ
y(x,y)=Asin(wt-kx)
v=sqrt(T/μ)
v=λ*f
The Attempt at a Solution
I already found to amplitude to be .199 m by taking the derivite of the wave equation and solving for A.
For part B, though the wave speed would simply be wavelength*frequency, but 20m/s is not the correct answer. I tried to mess around with a few other equations but they led me nowhere.
And for part C I know T is simply (v^2)*μ, but I obviously need to first find velocity.
Any help would be grealty appreciated, thanks!