- #1
jaumzaum
- 434
- 33
I was wondering if we could produce stationary waves in a vertical rope. There is a nice result we can get from a vertical rope that the pulse created from the lower extremity travels upwards with acceleration g/2 and the pulse created in the upper extremity travels downwards with acceleration -g/2. I was trying to get the equations of the stationary waves in a vertical rope (that is, if they exists), but I don't know if the most simple wave functions hold anymore.
For example, I was taught any wave can be written in the form:
$$y=f(x-vt)$$
But here the velocity is variable, so can we still write the above equation?
Also, will the amplitude remain constant?
I will write the result I got, but I don't know if they are correct, can anyone help me figure this out?
For the wave:
$$x=\frac{gt^2}{4}$$
$$\alpha=w\sqrt{4x/g}-wt+\phi$$
$$y=A sin(w\sqrt{4x/g}-wt+\phi)$$
For the stationary wave:
$$y_{stationary}=2A sin(w\sqrt{4x/g}+\phi) cos(wt)$$
For example, I was taught any wave can be written in the form:
$$y=f(x-vt)$$
But here the velocity is variable, so can we still write the above equation?
Also, will the amplitude remain constant?
I will write the result I got, but I don't know if they are correct, can anyone help me figure this out?
For the wave:
$$x=\frac{gt^2}{4}$$
$$\alpha=w\sqrt{4x/g}-wt+\phi$$
$$y=A sin(w\sqrt{4x/g}-wt+\phi)$$
For the stationary wave:
$$y_{stationary}=2A sin(w\sqrt{4x/g}+\phi) cos(wt)$$