PASCO WA-9867 Sine Wave Generator - Manual (Page 15)

Model No. WA-9867 Sine Wave Generator
15 ®
Experiment 1:
Standing Waves In Strings
Introduction
The general appearance of waves can be shown by means of standing waves in a string. This type
of wave is very important because most vibrations of extended bodies, such as the prongs of a
tuning fork or the strings of a piano, are standing waves. In this experiment you will discover how
the speed of the wave in a vibrating string is affected by the density of the string, the stretching
force and the frequency of the wave.
Theory
Standing waves (stationary waves) are produced by the interference of two traveling waves, both
of which have the same wavelength, speed and amplitude, but travel in opposite directions
through the same medium. The necessary conditions for the production of standing waves can be
met in the case of a stretched string by having waves set up by some vibrating body, reflected at
the end of the string and then interfering with the oncoming waves.
Equipment Part Number
Sine Wave Generator WA-9867
String Vibrator WA-9857
Braided String (inelastic, low-density) SE-8050 or similar
Yellow Braided Cord (inelastic, higher-density) ME-9409 or similar
Elastic Cord Part of WA-9857, SE-9409 or similar
Banana Patch Cords (qty. 2) SE-7123 or similar
Clamp or other device of securing the String Vibrator SE-7286 or similar
Super Pulley ME-9450
Mounting Rod for Super Pulley SA-9242
Universal Table Clamp ME-9472 or similar
Mass and Hanger Set ME-8967 or similar
Balance SE-8765A or similar
Tape Measure SE-8712A or similar
Strobe (optional) SF-9211 or similar