Stick-slip (or "slip-stick") refers to the phenomenon of a spontaneous jerking motion that can occur while two objects are sliding over each other.

## Cause

Stick-slip is caused by the surfaces alternatingly between a sticking to each other and sliding over each other, with a corresponding change in the force of friction. Friction is the Force resisting the relative motion of two Surfaces in contact or a surface in contact with a fluid (e Typically, the static friction coefficient between two surfaces is larger than the kinetic friction coefficient. Friction is the Force resisting the relative motion of two Surfaces in contact or a surface in contact with a fluid (e Friction is the Force resisting the relative motion of two Surfaces in contact or a surface in contact with a fluid (e If an applied force is large enough to overcome the static friction, then the reduction of the friction to the kinetic friction can cause a sudden jump in the velocity of the movement. In Physics, a force is whatever can cause an object with Mass to Accelerate.

The attached picture shows symbolically an example of stick-slip.

V is a drive system, R is the elasticity in the system, and M is the load that is lying on the floor and is being pushed horizontally. When the drive system is started, the Spring R is loaded and its pushing force against load M increases until the static friction coefficient between load M and the floor is not able to hold the load anymore. The load starts sliding and the friction coefficient decreases from its static value to its dynamic value. At this moment in fact the spring can give more power and accelerates M. During M’s movement, the force of the spring decreases, until it is insufficient to overcome the dynamic friction. At this point, the M stops. The drive system however continues, and the spring is loaded again etc.

## Examples

Examples of stick-slip can be heard from hydraulic cylinders, honing machines etc. A Hydraulic cylinder (also called a linear Hydraulic motor) is a mechanical Actuator that is used to give a linear Force through a linear stroke Special dopes can be added to the hydraulic fluid or the cooling fluid to overcome or minimize the stick-slip effect. Stick-slip is also experienced in lathes, mill centres, and other machinery where something slides on a slideway. Slideway oil typically lists "prevention of stick-slip" as one of their features. Other examples of the stick-slip phenomenon include the music that comes from a violin, the noise of car brakes and tires, and the noise of a stopping train. The violin is a bowed String instrument with four strings usually tuned in Perfect fifths It is the smallest and highest-pitched member A brake is a device for slowing or stopping the motion of a Machine or Vehicle, or alternatively a device to restrain it from starting to move again This article is about tires used on road Vehicles including pneumatic tires and solid tires. A train is a connected series of vehicles that move along a track ( Permanent way) to transport freight or passengers from one place to another Another example of the stick-slip phenomenon occurs when you play musical notes with a glass harp by rubbing a wet finger along the rim of a crystal wine glass. For the musical instrument see Glass harp and Glass harmonica. One animal that produces sound using stick-slip friction is the spiny lobster which rubs its antennae over smooth surfaces on its head.  [1]

Stick-slip can also be observed on the atomic scale using a friction force microscope[2]. A friction force microscope is an Atomic force microscope with a four quadrant photodetector which allows measuring the Frictional force acting on the probing tip In such case, the phenomenon can be interpreted using the Tomlinson model. Phenomenological model introduced in 1929 by the British physicist G

The behaviour of seismically-active faults is also explained using a stick-slip model, with earthquakes being generated during the periods of rapid slip. In Geology a fault, or fault line, is a planar rock fracture which shows evidence of relative movement An earthquake is the result of a sudden release of energy in the Earth 's crust that creates Seismic waves Earthquakes are recorded with a Seismometer

## References

1. ^ S. N. Patek (2001). Spiny lobsters stick and slip to make sound. Nature 411: 153–154. Nature is a prominent Scientific journal, first published on 4 November 1869 doi:10.1038/35075656. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.
2. ^ Atomic-scale friction of a tungsten tip on a graphite surface C. M. Mate, G. M. McClelland, R. Erlandsson, and S. Chiang Phys. Rev. Lett. 59, 1942 (1987)
Physical Review Letters is one of the most prestigious journals in Physics.
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