Fourth, fifth, and sixth derivatives of position

en.wikipedia.org

6 pointsthunderbong2 comments

Learnt something. As one of the linked articles says: "The higher derivatives of motion are rarely discussed in the teaching of classical mechanics of rigid bodies; nevertheless, we experience the effect not only of acceleration, but also of jerk and snap." [1]

Now I understand jerk as when you get pressed into your seat when starting a car. But how would I notice snap or even crackle?

[1] https://iopscience.iop.org/article/10.1088/0143-0807/37/6/06...

Yes, the change from not being pressed into your seat to being pressed into your seat is jerk. Basically the difference between two acceleration "levels".

Snap is how abrupt those changes between accelerations are. If you accelerate a bit, and then suddenly the light turns orange and you floor it, and the turbo kicks in, and your passengers go "woaaaaaah going to need a barf baaaaag" for example, it was probably not very smooth.

Sometimes instead of linear accelerations, those concepts can be easier to understand as changes in angular motions. You're on a curve of a certain radius, and suddenly the radius changes. The change is the jerk. How sudden the change happens is the snap.

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