Amplitude

In this picture, y is the amplitude of the wave

Different kinds of amplitudes

The amplitude or peak amplitude of a wave is a measure of how big its oscillation is.

Amplitudes are always measured as positive numbers (for example: 3.5, 1, 120) and are never negative (for example: -3.5, -1, -120). That's because distance can only be greater than zero or equal to zero; negative distance does not exist.

The distance from the top of one peak to the bottom of another is called peak-to-peak amplitude. Another way to describe peak-to-peak amplitude is to say that it is the distance between the maximum positive value and the maximum negative value of a wave is the maximum displacement of a wave from an equilibrium position

Amplitude Media

• 

  A sinusoidal curve*

  1. *
  2. Peak amplitude (\scriptstyle\hat u),*
  3. Peak-to-peak amplitude (\scriptstyle2\hat u),*
  4. Root mean square amplitude (\scriptstyle\hat u/\sqrt{2}),*
  5. Wave period (not an amplitude)*
• Envelope3.png

  Amplitude Envelope of Percussive and Flat Tones

Related pages

• Waves and their properties:
  • Frequency
  • Period
  • Wavelength
• Amplitude modulation
• Vibration control
• Vibration isolation