Jerk

:This article is about the physics concept of jerk. For other terms of jerk, see Jerk (disambiguation)

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In physics, jerk (in British English, jolt), also called surge, is the derivative of acceleration with respect to time (or the third derivative of displacement). Yank is mass times jerk, or equivalently, the derivative of force with respect to time. Jerk is a vector, and there is no generally used term to describe its scalar value.

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The units of jerk are metres per second cubed (m/s3). There is no universal agreement on the symbol for jerk, but j is commonly used.

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Jerk is used at times in engineering, especially when building roller coasters. Some precision or fragile objects—such as passengers, who need time to sense stress changes and adjust their muscle tension, or suffer e.g. whiplash—can be safely subjected not only to a maximum acceleration, but also to a maximum jerk. Jerk may be considered when the excitation of vibrations is a concern. A device which measures jerk is called a "jerkmeter."

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Higher derivatives of displacement than jerk also exist, but they are rarely necessary, and hence lack agreed names. Many suggestions have been made, such as jilt, jouse, and jolt, but such names have a disadvantage that they all begin with the same letter and can cause confusion in selecting their notations. To avoid this problem, some scientists favor the use of the terms snap, crackle, and pop for the 4th, 5th, and 6th derivatives of displacement, respectively, with some nonzero positive value for tongue-in-cheek.

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In development of the Hubble Space Telescope's pointing control system, the fourth derivative of position was considered and the engineers used the word jounce in their publications.

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Physics: Physics (from the Greek, φυσικός (phusikos), "natural", and φύσις (phusis), "nature") is the science of the natural world in the broadest sense, dealing with matter and energy and the fundamental forces of nature that govern the interaction...

British English: British English (BrE) is a term used loosely to refer to the form of the English language written in the British Isles, and more narrowly as spoken in the south of England (extending elsewhere with varying degrees). For historical reasons dating back to the rise of London in the 9th century, the var...

Derivative: In mathematics, the derivative is one of the two central concepts of calculus. (The other is the integral; the two are related via the fundamental theorem of calculus.)...

Jerk related Images and Photos (experimental)

The Jerk	The Jerk DVD (Widescreen)	Seinfeld - Jerk Store	The Jerk 1979
The Jerk 1979	Jerk Chicken Stand Negril Jamaica	Seinfeld The Jerk Store T-Shirt	Comic Cartoon - Hi Jerk Still Slinging It; Man Shoveling Poo
National Lampoon's Animal House / The Blues Brothers / The Jerk / Car Wash