Waves

• Displacement: the position of a particular point on a wave, at a particular instant in time, measured from the mean (equilibrium) position.

  Symbol: often x

  SI unit : m
• Amplitude: the magnitude of the maximum displacement reached by an oscillation in the wave.

  Symbol: A

  SI unit: m
• Frequency: the number of complete wave cycles per second. This may sometimes be measured as the number of complete waves passing a point per second.

  Symbol: f

  SI units: hertz, Hz
• Wavelength: the distance between a point on a wave and the same point on the next cycle of the wave, for example, the distance between adjacent wave peaks.
• Period: the time taken for one complete oscillation at one point on the wave. This will also be the time taken for the wave to travel one wavelength.

  Symbol: T

  SI unit: s
• Phase: the stage a given point on the wave is through a complete cycle. Phase is measured in angle units, as a complete wave cycle is considered to be the same as travelling around a complete circle, that is 360° or 2π radians.

  Symbol: no symbol

  SI unit: rad.
• Wave speed: the rate of movement of the wave- the same as speed in general.

  Symbol: v, or c for speed of electromagnetic waves.

  SI unit: m/s
• Wave speed equation:

  wave speed(m/s)=frequency (Hz) x wavelength (m)