Measure the frequency, wavelength and speed of waves in a solid
There are many different ways that the speed of waves in a solid can be measured. One method involves the use of a vibration generator.
Aim of the experiement
To measure the frequency, wavelength and speed of waves in a string.
- Attach a string or cord to a vibration generator and use a 200 gram (g) hanging mass and pulley to pull the string taut as shown in the diagram. Place a wooden bridge under the string near the pulley.
- Switch on the vibration generator and adjust the wooden bridge until stationary waves can be clearly observed.
- Measure the length of as many half wavelengths (loops) as possible, divide by the number of half wavelengths (loops). This is half the wavelength, doubling this gives the wavelength.
- The frequency is the frequency of the power supply.
- Calculate the speed of the waves using: wave speed = frequency × wavelength.
Example results table
|Number of half wavelengths||Length of X half wavelengths (cm)||Wavelength (cm)||Frequency (Hz)||Wave speed (cm/s)|
|Cord snapping||Damage to eyes||Eye protection / safety screen|