Waves

Make observations to identify the suitability of apparatus to measure the frequency, wavelength and speed of waves in a ripple tank

Materials

Method

1. Set up the ripple tank as shown in the diagram with about 5 cm depth of water.

2. Adjust the height of the wooden rod so that it just touches the surface of the water.

3. Switch on the lamp and motor and adjust until low frequency waves can be clearly observed.

4. Measure the length of a number of waves then divide by the number of waves to record wavelength. It may be more practical to take a photograph of the card with the ruler and take measurements from the still picture.

5. Count the number of waves passing a point in ten seconds then divide by ten to record frequency.

6. Calculate the speed of the waves using: wave speed = frequency × wavelength.