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  • Sound | Properties, Types, Facts | Britannica
    Sound, a mechanical disturbance from a state of equilibrium that propagates through an elastic material medium A purely subjective, but unduly restrictive, definition of sound is also possible, as that which is perceived by the ear Learn more about the properties and types of sound in this article
  • How Does Sound Travel? | Waves, Speed, Frequency, Amplitude - Britannica
    Sound travels in waves that are essentially disturbances that move through a medium by causing particles to vibrate back and forth in the direction of the wave’s travel Imagine a Slinky toy or a coiled spring: when you pull back one end and release it, a wave of compression and expansion of the coils travels along its length Similarly, sound waves consist of alternating compressions and
  • Wave motion | Definition, Examples, Types, Facts | Britannica
    Wave motion, propagation of disturbances—that is, deviations from a state of rest or equilibrium—from place to place in a regular and organized way Most familiar are surface waves on water, but both sound and light travel as wavelike disturbances, and the motion of all subatomic particles exhibits
  • Sound - Standing Waves, Frequency, Wavelength | Britannica
    Sound - Standing Waves, Frequency, Wavelength: This section focuses on waves in bounded mediums—in particular, standing waves in such systems as stretched strings, air columns, and stretched membranes The principles discussed here are directly applicable to the operation of string and wind instruments When two identical waves move in opposite directions along a line, they form a standing
  • Sound - Circular, Spherical, Waves | Britannica
    Sound - Circular, Spherical, Waves: The above discussion of the propagation of sound waves begins with a simplifying assumption that the wave exists as a plane wave In most real cases, however, a wave originating at some source does not move in a straight line but expands in a series of spherical wavefronts The fundamental mechanism for this propagation is known as Huygens’ principle
  • Ultrasonics | Physics, Sound Waves Applications | Britannica
    Ultrasonics, vibrations of frequencies greater than the upper limit of the audible range for humans—that is, greater than about 20 kilohertz The term sonic is applied to ultrasound waves of very high amplitudes Hypersound, sometimes called praetersound or microsound, is sound waves of frequencies
  • Transverse wave | Definition, Characteristics, Examples, Diagram . . .
    Transverse wave, motion in which all points on a wave oscillate along paths at right angles to the direction of the wave’s advance Surface ripples on water, seismic S (secondary) waves, and electromagnetic (e g , radio and light) waves are examples of transverse waves
  • Longitudinal wave | Physics, Sound Wave Motion | Britannica
    Longitudinal wave, wave consisting of a periodic disturbance or vibration that takes place in the same direction as the advance of the wave A coiled spring that is compressed at one end and then released experiences a wave of compression that travels its length, followed by a stretching; a point
  • Shock wave | Definition Facts | Britannica
    Shock wave, strong pressure wave in any elastic medium such as air, water, or a solid substance, produced by phenomena that create violent changes in pressure Shock waves differ from sound waves in that the wave front is a region of sudden and violent change





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