amplitude (physics)

Click a letter for the index

Or search the encyclopaedia:

 

 

Go

 

In physics, maximum variation of an oscillation from the equilibrium value. In a transverse wave motion, such as an ocean wave, it is the height of a crest (or the depth of a trough). In an electromagnetic wave (which is also transverse), it is the maximum intensity of the electric or magnetic field. For a longitudinal wave, such as a sound wave, amplitude is the maximum distance a particle moves from its resting position. A quiet sound has a lower amplitude and a loud sound has a higher amplitude. For a louder sound, more sound energy enters the ear every second. Amplitude is generally denoted by a.

AM (amplitude modulation) radio broadcasting is a method of transmitting audio-frequency signals. The amplitude of the low-frequency audio signal is made to modulate (vary slightly) the amplitude of a continuously transmitted radio carrier wave of a higher frequency. In this way the modulating signal is imprinted on the carrier wave.

The wingless dragon holds jewels in its claws to represent prosperity. Saffron yellow symbolizes the power of the monarchy. Orange-red stands for Buddhism. Effective date: c. 1971. >>