Topics to revise
Chemical analysis P2
Waves P2
Required practical - Ripple tank
2026 - This is the Wave 2 mocks week - try to complete these two topics if you can, if not catch up in half term.
Waves in a liquid or solid
Make observations to choose suitable apparatus and measure frequency, wavelength and speed of waves in a ripple tank and in a solid.
Check your understanding with these quick common questions. Use the drop down boxes to see the correct answers.
Waves in solids and liquids
Transverse waves can travel through solids. Transverse waves also travel on the surface of water (but not under water or air). This practical investigates waves on BOTH a ripple tank and in a string. Remember to revise the waves on a string as well, its rarer but catches more people out!. In the practical, you measure two values, e.g Wave speed and frequency and use these to calculate the third value using the wave equation.
This is a procedure, so you would not be asked to identify variables unless you were comparing two liquids etc.
Dependent variable - read the question carefully. The properties of waves change based on their frequency, wave length and wave speed. Each question may ask you to find a different value.
Waves on water
Ripple tank
Ruler
Camera
Waves on a string
Vibration generator
Masses (to maintain tension on a string)
A small wooden block to help change the length of a wave
Accuracy can be improved by: Ripple tank - a strobe light can be set to match the frequency of the waves. When the frequency of the strobe light matches the wave, it will appear to be stationary, making it easier to measure the wave length.
When measuring frequency - use a longer time to count the number of waves passing a point, e.g. 20 seconds rather than 1.
Other improvements: Repeat and calculate a mean.
Increasing the frequency gives a shorter wave length in both experiments
This is a procedure, so the focus is on giving a detailed method. Ensure you use a formula.
Remember a question will ask you to calculate one value and measure the other two, so use 2 of the methods below to calculate the third:
Use the formula wave speed = frequency x wave length
Frequency:
Count the number of waves passing a certain point in 10 seconds
Use the formula frequency = 1/time (this is on your equation sheet)
Use a stop watch
Wavelength
Place a ruler under the ripple tank
Use a camera to take a picture
Measure the distance between two waves. Repeat for at least 3 waves
Wave speed (velocity)
Measure the length of the tank with a ruler
Time with a stopwatch how long it takes a wave to travel the length of the tank
Use distance / time - wave speed
Repeat for 3 waves.
You could be asked how the frequency of a wave effects ifs wavelength
Use the formula wave speed = frequency x wave length
Frequency:
Change the frequency using the signal generator (this makes the string vibrate)
Use the masses to ensure the string is tight/taught.
Move the wooden bridge along the string until you get clear waves form
Change the frequency to get a range of values
Wavelength
Use a ruler to measure the wave length
Repeat for several waves