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If there exists something like that, then in $distance/time/time/time$, how is it expressed?

Steeven
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4 Answers4

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http://wordpress.mrreid.org/2013/12/11/jerk-jounce-snap-crackle-and-pop/

Speaking derivatives to time:

  • First position $x$,
  • then velocity $v=x'=\frac{dx}{dt}$,
  • then acceleration $a=x''=\frac{d^2x}{dt^2}$,
  • then jerk $x'''=\frac{d^3x}{dt^3}$,
  • then jounce/snap $x''''=\frac{d^4x}{dt^4}$,
  • then crackle $x'''''=\frac{d^5x}{dt^5}$,
  • then pop $x''''''=\frac{d^6x}{dt^6}$,
  • ...
Steeven
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7

Yes. Rate of change of acceleration is called jerk. Yes its dimensional formula is $[M^0, L^1, T^{-3}]$. Similarly one could also define higher time derivatives of acceleration if required for a particular problem.

user40330
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Yes. usually we name them $a'$ . and there can be even a speed of my $a'$ that I can call that $a''$ and it goes on like that.

it is only used it real life calculation that the calculation should be very precise like rocket science.

and the equation of displacement (with a constant $a'$) will be :

$$x =\frac16 a't^3 + \frac12 a_0t^2 + v_0t+x_0$$

(EDIT: also should mention sometimes they put a little dot on the a too instead of apostrophe )

Mobin
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1

An actual example in which there is a non-zero change in acceleration, that is, jerk, occurs is a spring. A spring's motion is described by a sinusoidal function. The derivative of a sinusoidal function is just another sinusoidal function. As a result, you can differentiate such a function infinitely many times, and will never have a derivative that's 0/a constant. So not only is there there a non-zero jerk in the motion of a spring, every single derivative of position is non-zero.