- #1
Corneo
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Hi I am working on a certain homework problem and I would appreciate some hint or inputs.
A rope, of length [itex]L[/itex], is attached to the ceiling and struck from the bottom at [itex]t=0[/itex]. The rope has negible stiffness, how long would it take for the wave to travel up the string and back down?
I have worked on the problem for a while and concluded that the velocity will vary because tension in the rope varies as you travel along the medium.
Tension, [itex]T[/itex], can be written as the distance from the bottom of the rope. That is [itex]T(x)=x \mu g[/itex], [itex]x[/itex] is the distance measured from the bottom of the rope; and [itex]\mu=m/L[/itex] is the linear mass density.
This is where I am lost. I think the wave equation is where I should start off, but not sure how to apply it to this problem
[tex]\frac {\partial ^2 y }{\partial t^2} = v^2 \frac {\partial ^2 y}{\partial x^2} = \frac {T(x)}{\mu} \frac {\partial ^2 y}{\partial x^2}= \frac {x \mu g}{\mu} \frac {\partial ^2 y}{\partial x^2} = x g \frac {\partial ^2 y}{\partial x^2}[/tex]
Any hints or inputs would be appreciated.
A rope, of length [itex]L[/itex], is attached to the ceiling and struck from the bottom at [itex]t=0[/itex]. The rope has negible stiffness, how long would it take for the wave to travel up the string and back down?
I have worked on the problem for a while and concluded that the velocity will vary because tension in the rope varies as you travel along the medium.
Tension, [itex]T[/itex], can be written as the distance from the bottom of the rope. That is [itex]T(x)=x \mu g[/itex], [itex]x[/itex] is the distance measured from the bottom of the rope; and [itex]\mu=m/L[/itex] is the linear mass density.
This is where I am lost. I think the wave equation is where I should start off, but not sure how to apply it to this problem
[tex]\frac {\partial ^2 y }{\partial t^2} = v^2 \frac {\partial ^2 y}{\partial x^2} = \frac {T(x)}{\mu} \frac {\partial ^2 y}{\partial x^2}= \frac {x \mu g}{\mu} \frac {\partial ^2 y}{\partial x^2} = x g \frac {\partial ^2 y}{\partial x^2}[/tex]
Any hints or inputs would be appreciated.