Answer:
When the string moves, it creates a very small change in the distance to the next point, th
Step-by-step explanation:
When the string moves, it creates a very small change in the distance to the next point, this generates a restoring force that tends to push the string back, this small disturbance propagates along the string and is what creates the pulse.
This is similar to what happens when a spring is stretched and a restoring force is generated shaved by the law of shortening.
F = k Dx