Waves

Waves are one of the ways in which energy may be transferred. Waves can be described as oscillations, or vibrations about a rest position. For example:

  • sound waves cause air particles to vibrate back and forth
  • ripples cause water particles to vibrate up and down

The direction of these vibrations is the difference between longitudinal or transverse waves. In longitudinal waves, the vibrations are parallel to the direction of wave travel. In transverse waves, the vibrations are at right angles to the direction of wave travel.

A ball vibrates rapidly. There are two arrows of equal length either side of the ball to represent vibration. One large arrow above the ball pointing right to show the direction of energy transfer.Longitudinal waves

A ball vibrates rapidly. There are two arrows of equal length either side of the ball to represent vibration. One large arrow next the ball pointing right to show the direction of energy transfer.Transverse waves

Mechanical waves cause vibrations of particles in a solid, liquid or gas and must have a medium to travel through.

curriculum-key-fact
All waves transfer energy but they do not transfer matter.