What is reflection?
In GCSE physics, reflection describes the behaviour of a wave when it meets a boundary between two media and does not pass through but stays in the original medium.
When a wave is reflected, the angle of incidence is always equal to the angle of reflection. This is known as the law of reflection. It can be shown most easily using a ray diagram, where a ray is a straight line indicating the direction of the wave.
The ray that approaches the boundary is known as the incident ray. The angle between the incident ray and the normal is known as the angle of incidence. The ray that leaves the boundary is known as the reflected ray. The angle between the reflected ray and the normal is the angle of reflection.
A ray diagram showing a wave reflected from a boundary. The angle of incidence is equal to the angle of reflection
Reflection revision resources to ace your exams
You can strengthen your understanding of reflection by using our revision notes tailored specifically for the AQA, Edexcel, OCR, and WJEC exam boards.
You can practice reflection questions and calculations with helpful guidance and examiner tips using our exam board specific GCSE Physics exam questions.
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