Investigating Waves (GCSE Physics)

Investigating Waves

Experiment to Investigate Waves

Method

1. We can investigate waves in solids. This can be done through the use of strings in the following experiment.
2. Gather all the equipment. For this experiment, you will need a frequency generator, a transducer, some string, a pulley and some masses.
3. Set up the equipment. Attach the pulley onto the edge of a desk. Place the masses onto one end of the string. This end should also rest on the pulley. Attach the other end of the string to a transducer, which in turn will be attached to the frequency generator.
4. Switch on the generator. Write down the frequency of the generator. Along with the transducer, this will make the string start to vibrate. This is also the frequency of the wave.
5. Increase the frequency. Slowly, start to increase the frequency of the generator. This will make the string start to vibrate faster, creating ‘loops’ on the string. These loops will make the shapes of the waves.
6. Measure several wavelengths. As the frequency increases, more loops will start to form. Each loop is equivalent to half a wavelength. Once there are about 5 or 6 loops (half wavelengths), measure the length of string from the start to the end.
7. Calculate one wavelength. Now we have a measurement for 5 or 6 half wavelengths, we can calculate the length of one half wavelength. To find one wavelength, we simply multiply this value by 2.
8. Use the equation. Now that we have values for both the frequency (from the generator) and the wavelength, we can use our equation v = fλ to calculate wave speed.