Sally and a partner holds the ends of a spring 4 meters apart. There are 5 nodes in the standing wave produced. Sally moves her hand from the rest position back and forth along the floor 20 times in 4 seconds.

Question

Sally and a partner holds the ends of a spring 4 meters apart.  There are 5 nodes in the standing wave produced.  Sally moves her hand from the rest position back and forth along the floor 20 times in 4 seconds.
Determine the following:
Wavelenght of wave sally sue sent
Frequence of wave produced
Speed of wave

drwls · Answer

The distance between nodes of the standing wave pattern is a half wavelength. Therefore the wavelength is 2*4m/5 = 1.6m

The frequency of the traveling waves is 20/4 = 5 Hz

Wave speed = wavelength * frequency
= __ m/s