# Explain how the amplitude and frequency of a wave are related to the energy it carries, and distinguish between the effect of increasing amplitude and increasing frequency on the energy transported by a mechanical wave travelling through a medium.

> IB DP Physics Higher Level (2023 syllabus) — C.2 Wave model · Explain · 4 marks

## Mark scheme (4 marks)

1. The energy carried by a wave is proportional to the square of its amplitude.
2. The energy carried by a wave is also proportional to the square of its frequency.
3. Increasing the amplitude increases the maximum displacement of the particles in the medium, so each particle has greater kinetic and potential energy as it oscillates.
4. Increasing the frequency increases the rate at which energy is transferred because particles complete more oscillations per unit time, so the power (energy per unit time) delivered by the wave is greater.

## Key terms

- [amplitude](https://www.gradenine.co.uk/glossary/amplitude)
- [frequency](https://www.gradenine.co.uk/glossary/frequency)
- [energy](https://www.gradenine.co.uk/glossary/energy)
- [mechanical wave](https://www.gradenine.co.uk/glossary/mechanical-wave)

## Related

- [Revision notes for IB DP Physics Higher Level (2023 syllabus)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-how-the-amplitude-and-frequency-308952c9) · Published by Druglandscape Ltd.