The curve y fx is shown in the figure at the right A1 A pul

The curve y = f(x) is shown in the figure at the right.

A1. A pulse with this shape is started on a long stretched spring; that is, at time t = 0, the spring has the shape y(x,0) =f(x).
What is the function, y(x,t) that describes the shape of the spring at a time t if this pulse moving to the right with the speed c?

y(x,t) =______

A2. A demonstrator holds a long stretched spring at one end and generates a pulse moving down the string by moving his hand up and back to its starting point quickly. The speed of pulses moving on the spring is 250 cm/s and he moves his hand up and down in 0.5 s. Is it possible to predict the width of the pulse that moves along the spring?

Yes or No or It is impossible to choose from the information given

If you can do it, find the value and put it in the box below. If you can\'t, put the number 0.

______ cm

Solution

A.1

y(x,t) = f(x - ct)

A.2

Yes. It can be predicted. width = wavelength = v T = 250 cm/s x 0.5 s = 125 cm