Pulse Traveling on an Elastic String
Pulse Traveling on an Elastic String
This Demonstration shows the behavior of a pulse (a local deformation) in an elastic string. The pulse travels at a constant speed in the positive direction, so that at any instant only a limited region of the string is disturbed. Do not confuse the speed of the pulse with the velocity of a point in the propagation medium, shown by the red point on the elastic string.
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The function describing the pulse is , where is the speed of the pulse in the direction . The position (black line) of a specific point in the propagation medium (red point) is obtained by fixing the position and changing the time in the function . The velocity (blue line) and acceleration (brown line) of this point are given by the first and second derivatives of the function over time, respectively.
y(x,t)=f(x-vt)
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In this Demonstration we see the pulse traveling along the positive direction in the bottom panel. The position , velocity , and acceleration of the red point over the elastic string are show in the upper panel; the acceleration is zero at points where the velocity is a maximum.
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