Light & Sound Waves (Edexcel IGCSE Physics (Modular))

Light

• Visible light is a part of the Electromagnetic spectrum which means it is a transverse wave

  • This is explained in Transverse & longitudinal waves

Representing a transverse wave

Light waves are transverse: the particles vibrate in a perpendicular direction to the energy transfer

• Light can undergo:

  • Reflection

  • Refraction

Sound

• Sound waves are longitudinal waves

  • This is explained in Transverse & longitudinal waves

• Longitudinal waves are usually drawn as several lines to show that the wave is moving parallel to the direction of energy transfer

  • Drawing the lines closer together represents the compressions

  • Drawing the lines further apart represents the rarefactions

Representing a longitudinal wave

Longitudinal waves are represented as sets of lines with rarefactions and compressions

• Sound can also undergo:

  • Reflection

  • Refraction

• The reflection of a sound wave is called an echo