Interference
Quantum and Nuclear | Light, Sound and Waves

Start with water waves

Teaching Guidance for 14-16 Supporting Physics Teaching

Water waves and ripple tanks

There is a long tradition of starting with water waves when teaching about waves and radiation in physics. This makes a lot of sense because, unlike with light and sound, it is possible actually to see the water waves being reflected, refracted, diffracted and interfering.

In addition, the first hand nature of water waves is a good starting point for explaining interference effects with:

  • Constructive interference leading to the creation of double-sized water waves
  • Destructive interference leading to flat water

It would be worth checking to see whether your school has a ripple tank that can be used to demonstrate all of these effects.

Teacher Tip: You'll need to practice, and to pay particular attention to the setting up instructions – getting the depth of the water correct is often crucial.

2023 IOP Awards

Teachers of Physics Awards

Recognising and celebrating outstanding contributions to the field of physics education.

Learn more