PASCO WA-9857 String Vibrator - Manual (Page 16)

String Vibrator Wave Speed
16 ®
4. Start recording data just before you pluck the string, then immediately stop recording.
5. View the force and voltage data on a graph, and find the elapsed time,
∆t, between the sudden
decrease in tension and the change in voltage.
6. Calculate the pulse speed:
(eq. 3)
Conclusions
You have calculated the wave speed using three methods.
1) Compare your results. Are the similar? If they deviate from one another, can you explain
why?
2) Which method do you think is the most accurate? Explain why.
Further Investigation
Repeat this experiment with a different length of cord (you will find that the tension to achieve a
standing wave will be different). Before you measure v using the three methods, predict how the
results will differ from your initial findings.
v
L
∆t
----- =