What happens to frequency during refraction?

Frequency is unchanged because it is set by the source; the speed and wavelength change together.

What is the difference between transverse and longitudinal waves?

Transverse waves oscillate perpendicular to the direction of travel, longitudinal waves oscillate parallel to it, as sound does.

PhysicsGCSE, IGCSE & A Level

Wave speed is how fast a wave transfers energy through a medium, equal to frequency multiplied by wavelength.

When a wave crosses into a new medium its speed and wavelength change but its frequency stays the same — the key to explaining refraction.

For all electromagnetic waves in a vacuum the speed is

3.0 \times 10^{8}\,\text{m s}^{-1}

, so wavelength and frequency are inversely proportional.

v = f\lambda

A sound wave of frequency

500\,\text{Hz}

and wavelength

0.68\,\text{m}

travels at

340\,\text{m s}^{-1}

Convert wavelengths given in nanometres or centimetres to metres before substituting; unit conversion errors dominate this topic.

What happens to frequency during refraction?: Frequency is unchanged because it is set by the source; the speed and wavelength change together.
What is the difference between transverse and longitudinal waves?: Transverse waves oscillate perpendicular to the direction of travel, longitudinal waves oscillate parallel to it, as sound does.

Refraction is the change in direction of a wave as it crosses a boundary between media, caused by a change in its speed.

Frequency is the number of complete waves or oscillations passing a point each second, measured in hertz.

Take wave speed from a definition to full marks with exam-board question banks, revision notes and instant step-by-step feedback from Study Coach.

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