Can you solve for delta d in jerk motion using this formula?

  • Context: Graduate 
  • Thread starter Thread starter RobotGymnast
  • Start date Start date
  • Tags Tags
    Jerk Motion
Click For Summary

Discussion Overview

The discussion revolves around determining the formula for calculating delta d in the context of jerk motion, involving variables such as time (t), initial velocity (v1), initial acceleration (a1), and constant jerk (J). The scope includes kinematics and the implications of constant jerk on motion equations.

Discussion Character

  • Exploratory
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • One participant asks for the appropriate formula to solve for delta d in relation to t, v1, a1, and constant J.
  • Another participant requests clarification on symbols and context, mentioning the concept of impulse.
  • A participant proposes a kinematic equation for delta d, suggesting it should account for constant jerk rather than constant acceleration.
  • There is a discussion about the relationship between force, mass, and jerk, with one participant stating that if force is constant, acceleration can be derived from jerk.
  • One participant corrects themselves to clarify that jerk is the derivative of acceleration.
  • A participant suggests an equation that incorporates jerk into the kinematic equations, proposing a term for jerk motion.
  • Another participant expresses confusion over differing results obtained by substituting equations, noting a discrepancy in the coefficients related to jerk when integrating.

Areas of Agreement / Disagreement

Participants express differing views on the correct formulation for delta d in jerk motion, with no consensus reached on the final equation or the correct coefficient for the jerk term.

Contextual Notes

There are unresolved assumptions regarding the definitions of the variables and the conditions under which the formulas apply, particularly concerning the treatment of jerk and its integration.

RobotGymnast
Messages
4
Reaction score
0
What formula would one use to solve for delta d with regards to t, v1, a1, and constant J?
 
Physics news on Phys.org
RobotGymnast said:
What formula would one use to solve for delta d with regards to t, v1, a1, and constant J?

Please define your symbols, and provide the context of your question. Are you familiar with the concept of an impulse?

http://en.wikipedia.org/wiki/Impulse

.
 
Kinematics. As in,
Code:
delta d = vt + (1/2)at[SUP]2[/SUP]

except assuming that jerk motion is constant, rather than acceleration.
 
Last edited:
Assuming that the mass is constant, if the force of the jerk J is constant, considering that F = ma so J = ma so a = J/m since J and m are constant A is constant.

So if your implying there is an acceleration in place before the jerk, you would use vector addition to figure out the resultant acceleration. And use your formula to solve for d.
 
*jerk motion (the derivative of acceleration). whoops.
 
Well, going from the equation using velocity [tex]s=v t[/tex], to the equation using acceleration [tex]v t + \frac{1}{2}a t^2[/tex] I would assume that the equation using jerk is [tex]s=v t + \frac{1}{2}a t^2 + \frac{1}{6}j t^3[/tex].

There's my guess.
 
That's what I got. What confuses me was that I also got a different answer by substituting physics equations into one another. I ended up getting ¼ Jt^3 rather than 1/6 Jt^3. But integrating the equation for jerk motion twice gives the answer you gave, which I think is correct.
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 10 ·
Replies
10
Views
9K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 15 ·
Replies
15
Views
2K
  • · Replies 15 ·
Replies
15
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K