VIBRATIONS
Noun
vibrations
plural of vibration
Source: Wiktionary
VIBRATION
Vi*bra"tion, n. Etym: [L. vibratio: cf. F. vibration.]
1. The act of vibrating, or the state of being vibrated, or in
vibratory motion; quick motion to and fro; oscillation, as of a
pendulum or musical string.
As a harper lays his open palm Upon his harp, to deaden its
vibrations. Longfellow.
2. (Physics)
Definition: A limited reciprocating motion of a particle of an elastic body
or medium in alternately opposite directions from its position of
equilibrium, when that equilibrium has been disturbed, as when a
stretched cord or other body produces musical notes, or particles of
air transmit sounds to the ear. The path of the particle may be in a
straight line, in a circular arc, or in any curve whatever.
Note: Vibration and oscillation are both used, in mechanics, of the
swinging, or rising and falling, motion of a suspended or balanced
body; the latter term more appropriately, as signifying such motion
produced by gravity, and of any degree of slowness, while the former
applies especially to the quick, short motion to and fro which
results from elasticity, or the action of molecular forces among the
particles of a body when disturbed from their position of rest, as in
a spring. Amplitude of vibration, the maximum displacement of a
vibrating particle or body from its position of rest.
– Phase of vibration, any part of the path described by a particle
or body in making a complete vibration, in distinction from other
parts, as while moving from one extreme to the other, or on one side
of the line of rest, in distinction from the opposite. Two particles
are said to be in the same phase when they are moving in the same
direction and with the same velocity, or in corresponding parts of
their paths.
Source: Webster’s Unabridged Dictionary 1913 Edition