Daniel A. Russell, Graduate program in Acoustics, The Pennsylvania State university

This job-related by Dan Russell is licensed under a an imaginative Commons Attribution-NonCommercial-NoDerivatives 4.0 international License.Based ~ above a work at http://www.invernessgangshow.net/drussell/demos.html.

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The content of this web page was originally posted on august 26, 1998. Animations were last updated on August 5, 2016. The HTML password was modified to it is in HTML5 compliant on in march 18, 2013.

Longitudinal and Transverse wave Motion

Mechanical Waves are waves i beg your pardon propagate v a material medium (solid, liquid, or gas) in ~ a wave speed which relies on the elastic and inertial nature of that medium. There space two an easy types that wave movement for mechanical waves: longitudinal waves and transverse waves. The animations listed below demonstrate both varieties of wave and also illustrate the difference between the activity of the wave and the activity of the particles in the tool through i m sorry the wave is travelling.

The adhering to animations were developed using a modifed variation of the Mathematica® Notebook " Sound Waves" by carpet Bengtsson.

Longitudinal tide

In a longitudinal wave the bit displacement is parallel come the direction of wave propagation. The animation at right shows a one-dimensional longitudinal aircraft wave propagating under a tube. The particles perform not move down the tube through the wave; they simply oscillate earlier and forth around their individual equilibrium positions. Pick a single particle and watch its motion. The tide is viewed as the motion of the compressed an ar (ie, it is a pressure wave), which moves from left to right.

The second animation at right shows the difference in between the oscillatory motion of individual particles and the propagation that the wave v the medium. The animation additionally identifies the regions of compression and also rarefaction.The p waves (Primary waves) in an earthquake are instances of Longitudinal waves. The ns waves travel v the faster velocity and also are the very first to arrive.

To watch a animations the spherical longitudinal waves inspect out: Sound Radiation from straightforward Sources Radiation indigenous Cylindrical Sources

In a transverse wave the particle displacement is perpendicular to the direction of tide propagation.The animation below reflects a one-dimensional transverse airplane wave propagating indigenous left come right. The particles do not move in addition to the wave; they simply oscillate up and also down about their separation, personal, instance equilibrium positions as the tide passes by. Choose a single particle and watch the motion.

The S tide (Secondary waves) in one earthquake are instances of Transverse waves. S tide propagate with a velocity slower than P waves, getting here several seconds later.


Water waves are an instance of waves the involve a combination of both longitudinal and transverse motions. Together a tide travels v the waver, the particles travel in clockwise circles. The radius the the one decreases as the depth right into the water increases. The computer animation at right mirrors a water wave travelling indigenous left to right in a region where the depth that the water is greater than the wavelength the the waves. Ns have established two particles in orange to show that every particle undoubtedly travels in a clockwise circle as the tide passes.

Another example of waves v both longitudinal and also transverse motion may be discovered in solids together Rayleigh surface ar waves (named after man W. Strutt, third Baron Rayleigh who very first studied castle in 1885). The corpuscle in a solid, through which a Rayleigh surface ar wave passes, move in elliptical paths, with the major axis the the ellipse perpendicular to the surface of the solid. Together the depth into the solid boosts the "width" that the elliptical route decreases.

Rayleigh waves in one elastic solid are different from surface waves in water in a very important way. In a water wave all particles take trip in clockwise circles. However, in a Rayleigh surface wave, corpuscle at the surface ar trace the end a counter-clockwise ellipse, while particles at a depth of an ext than 1/5th of a wavelength trace out clockwise ellispes. This movement is often referred to as being "retrograde" due to the fact that at the surface, the horizontal component of the particle activity is in opposing direction as the wave propagation direction. I have identified two particles in orange in this computer animation to illustrate the retrograde elliptical path at the surface and the reversal in the direction of activity as a function of depth.

The Rayleigh surface waves room the waves that cause the most damage during an earthquake. They travel through velocities slower 보다 S waves, and also arrive later, but with much better amplitudes. These are additionally the waves that space most conveniently felt during an earthquake and involve both up-down and side-to-side motion.

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Update (Aug. 5, 2016): thanks to Dongyao Li (graduate college student at the university of Illinois, Urbana-Champaign) who asked questions resulting in a much improved version the this animation.