/am"pli toohd', -tyoohd'/, n.1. the state or quality of being ample, esp. as to breadth or width; largeness; greatness of extent.2. large or full measure; abundance; copiousness.3. mental range, scope, or capacity.4. Physics. the absolute value of the maximum displacement from a zero value during one period of an oscillation.5. Elect. the maximum deviation of an alternating current from its average value.6. Astron. the arc of the horizon measured from the east or west point to the point where a vertical circle through a heavenly body would intersect the horizon.7. Math. argument (def. 8b).[1540-50; < L amplitudo. See AMPLE, -I-, -TUDE]
* * *▪ physicsin physics, the maximum displacement or distance moved by a point on a vibrating body or wave measured from its equilibrium position. It is equal to one-half the length of the vibration path. The amplitude of a pendulum is thus one-half the distance that the bob traverses in moving from one side to the other. Waves are generated by vibrating sources, their amplitude being proportional to the amplitude of the source.For a transverse wave, such as the wave on a plucked string, amplitude is measured by the maximum displacement of any point on the string from its position when the string is at rest. For a longitudinal wave, such as a sound wave, amplitude is measured by the maximum displacement of a particle from its position of equilibrium. When the amplitude of a wave steadily decreases because its energy is being lost, it is said to be damped.
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