Questions tagged [jerk]

Jerk is the third derivative of displacement with respect to time. It is also the derivative of acceleration with respect to time.

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46
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Why does one experience a short pull in the wrong direction when a vehicle stops?

When you're in a train and it slows down, you experience the push forward from the deceleration which is no surprise since the force one experiences results from good old $F=m a$. However, the moment ...
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What would happen if $F=m\dot{a}$?

What would happen if instead of $F=m*d^2x/dt^2$, we had $F=m*d^3x/dt^3$ or higher? Intuitively, I have always seen a justification for $\sim 1/r^2$ forces as the "forces being divided equally over ...
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What came first, Rice Crispy or “Snap,” “Crackle,” and “Pop”? [closed]

The fourth, fifth, and sixth derivatives of position are called "Snap" "Crackle" and "Pop". What came first, the rice crispy characters, or the physics units?
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Applying energy and momentum conservation to the problem of pulling a bent carpet at a constant speed

Consider this system. A long, thin, pliable carpet is laid on a floor. One end of the carpet is bent back and then pulled backwards with constant speed $v$, just above the part of the carpet ...
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Is it possible to have a rate of change of acceleration?

I know this may seem a weird question, but it always bothers me. My physics book (Resnick,Halliday,Walker), and also various sites never say anything beyond acceleration. But when a moving body is ...
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How to brake 'beautifully'?

Sometimes when I'm driving my car, I play a "game" against myself in which I try to minimize the deceleration felt by passengers (including myself) while still braking in a reasonable short space. I ...
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How do I calculate the distance a ship will take to stop?

I am a River Pilot and drive ships for a living. These ships are very large and range up to 160,000 Metric Tons. I am trying to figure out how to calculate the distance to stopping. I have a basic ...
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What is the best path for a given initial and final state?

I am trying to calculate an efficient acceleration curve given starting and final positions and velocities. I'm assuming no friction, and that the acceleration can be applied in any direction at any ...
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Why don't we consider jerk in physics classes? [duplicate]

When I got more into physics, I started asking myself if just like acceleration represents the growth of speed, something else could also represent the growth of acceleration itself. And it came that ...
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Kinematic equation as infinite sum

I'm not sure exactly how to phrase this question, but here it goes: $v=\dfrac{dx}{dt}$ therefore $x=x_0+vt$ UNLESS there's an acceleration, in which case $a=\dfrac{dv}{dt}$ therefore $x=x_0+v_0t+\...
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Upper limits for jerk and higher derivatives in physics

Is there an upper limit for jerk in physics? What about higher derivatives? A consequence of special relativity is that no material body can reach or exceed the speed of light in vacuum (due to ...
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High speed does not kill. Does acceleration do it ? or jerk?

In a recent question the OP asked why high speed will not kill us. The accepted answer, highly upvoted, stated very first that Speed doesn't kill us, but acceleration does. The second answer (...
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Bidirectional jerk motion on a stopping vehicle

A stopping vehicle (say a car) has an apparent retardation (which may/may not be constant in magnitude) when force via brakes is applied. I travel by subway trains, and I noticed an odd phenomenon. ...
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Is there any case in physics where the equations of motion depend on high time derivatives of the position?

For example if the force on a particle is of the form $ \mathbf F = \mathbf F(\mathbf r, \dot{\mathbf r}, \ddot{\mathbf r}, \dddot{\mathbf r}) $, then the equation of motion would be a third order ...
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Physical intuition for higher order derivatives

Could somebody give me an intuitive physical interpretation of higher order derivatives (from 2 and so on), that is not related to position - velocity - acceleration - jerk - etc?
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In mechanics, is shock really better expressed as jerk instead of acceleration?

Some expensive electronics or mechanical devices are designed to be shock-resistant. However, the manufacturers often market the level of shock-resistance in units of g-force (I know g-force is really ...
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When motion begins, do objects go through an infinite number of position derivatives?

This might be a very vague and unclear question, but let me explain. When an object at rest moves, or moves from point $A$ to point $B$, we know the object must have had some velocity (1st derivative ...
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Relativity of Jerk

Popular expositions of general relativity start with a thought experiment showing that it is impossible to distinguish a constantly accelerating frame of reference in a free fall from a free floating ...
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Is there jerk on Uniform Circular Motion? [duplicate]

I was reading my textbook and I encountered a section where it explains that Centripetal Acceleration is not constant, thus, I wonder if jerk exists in Uniform Circular Motion? The textbook states ...
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Is there any such thing as a change in acceleration (ex: 3 m/s/s/s)? [duplicate]

If there exists something like that, then in $distance/time/time/time$, how is it expressed?
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1answer
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What is the highest order physically observable derivative of position?

Are there any physical models that compute higher-order derivatives of position than jerk, snap, crackle, pop, etc.? Can we measure higher-order, non-zero components?
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How are jerk equations connected to chaos theory?

I read in this Wikipedia article: It has been shown that a jerk equation, which is equivalent to a system of three first-order, ordinary non-linear differential equations, is the minimal setting ...
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What would prevent object from experiencing an infinitely powerful jerk in an instant?

Unlike speed which is capped for anything with rest mass at speed of light in a vacuum, what would prevent an object to undergo infinite acceleration in an instant? I assume in theory if we can apply ...
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What are the equations for motion with constant jerk?

Every one knows the three famous equations for motions with constant acceleration . But what if the motion were having a jerk? How should then be the equations for motions? How can I find them?
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Are there experimental observations of the Abraham-Lorentz force?

The Abraham-Lorentz force is the force a classical charged particle particle exerts on itself due to its own electromagnetic field. It has a rather simple formula that reads $$ \vec{F}_\mathrm{AL} = \...
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Understanding a rotational system with centripetal snap, angular jerk, and a third-dimensional tension vector

In a recent experiment in my physics class, we were given the task of finding the experimental rotational moment of inertia in a T-stand with two masses attached to the ends of a certain length. I ...
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Is the Hamiltonian of a relativistic charged particle in an electromagnetic field only an approximation?

Consider a system of two relativistic charged point particles 1 and 2 which interact through their electric and magnetic fields. The equation of motion for the first particle is then given by the ...
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1answer
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finding velocity along a curve with kinematic equations using time

(i'm "not" looking for coding help. i need help setting up the math.) i'm writing a program for a physics class to find the velocity of an object across a random curve. where the only force acting on ...
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1answer
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Calculating jerk vs Fitts law for smoothness

I've tracked the movement of an input method resulting in this dataset. All data is tracked with equal intervals of $100 \, \mathrm{ms}$. For example an iteration value of 4 means that this is the ...
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Jerk Magnitudes and Earthquakes

Destruction from earthquakes depends on many factors, including magnitude, occurrence depth and closeness to epicenter. One measure that may relate destructive force for buildings and infrastructure ...
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Computing distance traveled from jerk

When dealing with higher time derivatives like jerk, how does one find the distance traveled? Can it be calculated by just knowing time?
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Non-zero higher time derivatives of position?

My mom told me to use speed control, which would allow the car to remain at constant speed. I told her that its impossible for a car to maintain constant speed, as slight changes in friction on the ...
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Pushing down on the gas pedal of a car a good example of jerk?

I'm trying to think of the clearest examples to demonstrate the concept of jerk to a layman. Ignoring drag and making other reasonable assumptions (friction is conveniently there to only allow you to ...
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How are the higher derivatives (jerk, jounce) of position with respect to time used in physics? [duplicate]

I don't see them much in any physics lesson or course, but that's probably because I'm not into physics as much. I can understand why velocity and acceleration are useful, but why would someone want ...
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1answer
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What is $mass \cdot jerk$, or yank?

So if Momentum is $m \cdot v$, Force is $m \cdot a$, and Jerk is $\frac{\Delta a}{\Delta t}$ what is $m \cdot j$? I've read that the name for this is yank, but I'm curious as to what it is ...
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1answer
386 views

Real world intuitive explanation of Jerk

If $a(t)$ denotes the acceleration of an object, then $a^\prime(t)$ represents the jerk. I'm looking for an intuitive explanation of this phenomena. I'm hoping the following anecdote provides the ...
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1answer
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Do we actully feel a change in acceleration?

Let's say you were in a sports car with your foot to the floor racing at maximum acceleration then all of a sudden you completely stop accelerating and maintain the speed you are going. Would you ...
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1answer
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High order (>3) derivatives measurements

Is it possible to directly measure derivatives of higher order than 3? It can be jerk for instance. By "directly" I assume that we can measure a signal proportional to the jerk value without ...
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Relationship between velocity and position due to constant jerk proof check [closed]

In constant accelaration and linear (1D) motion, we can show that relationship between velocity and position is quadratic (parabola) by We can write $v$ in the form of $v=v(x(t))$ \begin{equation} a=\...
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1answer
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Can the jerk diverge?

In other words can the acceleration change instantly? In direction and/or magnitude. There are two aspects to this question. In a problem, can you treat acceleration as changing instantly? (when in ...
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1answer
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How to determine the minimum “Arrival Distance” given a maximum velocity, acceleration and jerk along with an initial velocity and acceleration?

Problem Given the following: $A$ - maximum acceleration. $J$ - constant jerk (the rate of change of acceleration). $v$ - initial velocity. $a$ - initial acceleration (where, in practice, $a ∈ [-A, A]$...
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“The state-space for a single particle in classical space is 6-dimensional” — Is this wrong?

The general argument is as follows. By Newton's second law $\mathbf F=m\ddot{\mathbf{x}}$. Now it is said that this is a second-order ODE and hence requires $\mathbf x(0)$ and $\mathbf{\dot{x}}(0)$ as ...
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Can gravity induce any jerk?

The equivalence principle states that constant acceleration inside a closed elevator is indistinguishable from gravitational force. But prior to its reaching constant acceleration, any elevator has ...
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Position, velocity, acceleration, jolt, and [duplicate]

I am familiar with the fact that $\displaystyle{\frac{dx}{dt}}=v$, $\displaystyle{\frac{dv}{dt} =a}$, and $\displaystyle{\frac{da}{dt}=J}$ where $J$ denotes the 'jolt', or jerk. Are further ...
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Higher order versions of momentum? Can conservation principles be established and used? [closed]

Question Can higher order derivatives of momentum be useful in creating theories of dynamics if they have conservation principles? Even if they aren't needed, could it be done in theory? For instance,...
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Calculate kinematics of body movement from the set of spatial coordinates

Short intro I have a set of 3D (x,y,z) spatial coordinates of arm movement obtained using motion capture system. The example set of such coordinates looks like this (rounded up): ...
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When we take time derivative of a function of time, then is the result another function of time, again?

(I'll try to explain my question by one known example), for example where the velocity is a function of time v(t) then its time derivative (which is acceleration: $a=\frac {dv}{dt}$) is another ...
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Stresses in asteroid during close flyby

The acceleration of an asteroid (such as 2012DA14) as it approaches earth is proportional to the reciprocal of distance $r$ from earth center, squared. the derivative of the acceleration, or jerk, is ...
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1answer
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Is the four-jerk time-like or space-like?

In the paper Dynamics of a Charged Particle the author claims after equation (10): However, this equation is mathematically inconsistent because both $\dot v^\mu$ and $\dot F^\mu$ are spacelike ...