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marginalia_nu ◴[] No.40727129[source]
Do these higher order derivatives say anything meaningful?

I always got the sense from physics that outside of purely mathematical constructions such as Taylor series, higher order time derivatives aren't providing much interesting information. Though I'm not sure whether this is the inherent laziness of physicist math[1] or a property of the forces in nature.

[1] since e^x = 1 + x is generally true, why'd you even need a second order derivative

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fellerts ◴[] No.40727207[source]
Jerk (how fast acceleration changes) is useful. I've found being a passenger in newer electric buses to pose more challenges than ICE buses because EVs can change their acceleration so rapidly. While their maximum acceleration isn't very high, they can go from standstill to accelerating in a split second, toppling anyone standing unless they hold on to something. ICEs need more time to reach maximum acceleration. In other words, EVs jerk more.
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itsoktocry ◴[] No.40727540[source]
>they can go from standstill to accelerating in a split second

Every car can go from a standstill to accelerating in a split second.

>their maximum acceleration isn't very high

What is the maximum acceleration of an EV? Do you have some numbers?

>ICEs need more time to reach maximum acceleration

I don't think what you're describing is jerk, it's acceleration (and velocity).

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1. fellerts ◴[] No.40728399{3}[source]
> Every car can go from a standstill to accelerating in a split second

Going from a standstill to accelerating at say 3 m/s² is very different in a normal ICE car vs. an EV. It's anecdotal, but you must have noticed this if you've driven an EV before.

> What is the maximum acceleration of an EV?

I was talking specifically about the electric buses in my city. They don't have massive acceleration compared to, say, a Tesla.

> I don't think what you're describing is jerk

I am talking about how rapidly electric buses change acceleration. That's the definition of jerk.