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Physics

Key Terms

PhysicsKey Terms

Key Terms

amplitude
the amount that matter is disrupted during a sound wave, as measured by the difference in height between the crests and troughs of the sound wave.
beat
a phenomenon produced by the superposition of two waves with slightly different frequencies but the same amplitude
beat frequency
the frequency of the amplitude fluctuations of a wave
damping
the reduction in amplitude over time as the energy of an oscillation dissipates
decibel
a unit used to describe sound intensity levels
Doppler effect
an alteration in the observed frequency of a sound due to relative motion between the source and the observer
fundamental
the lowest-frequency resonance
harmonics
the term used to refer to the fundamental and its overtones
hearing
the perception of sound
loudness
the perception of sound intensity
natural frequency
the frequency at which a system would oscillate if there were no driving and no damping forces
overtones
all resonant frequencies higher than the fundamental
pitch
the perception of the frequency of a sound
rarefaction
a low-pressure region in a sound wave
resonance
the phenomenon of driving a system with a frequency equal to the system's natural frequency
resonate
to drive a system at its natural frequency
sonic boom
a constructive interference of sound created by an object moving faster than sound
sound
a disturbance of matter that is transmitted from its source outward by longitudinal waves
sound intensity
the power per unit area carried by a sound wave
sound intensity level
the level of sound relative to a fixed standard related to human hearing
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