We can perceive position, velocity, acceleration, jerk

In summary, we can perceive position by establishing a reference point, velocity by noticing a change in position, acceleration by noticing a change in velocity, and jerk by noticing a change in acceleration. However, there is a limit to how many derivatives we can perceive and take into account, as we are limited beings. Our senses rely on position, velocity, and acceleration, and we often consider constant jerk to simplify things. In physics, we aim to find the simplest explanation for a phenomenon, and in classical motion, we only need to know position, velocity, and acceleration to understand it.
  • #1
DarkFalz
71
0
We can perceive position by establishing a reference point
We can perceive velocity by noticing a change in position
We can perceive acceleration by noticing a change in velocity
We can perceive jerk by noticing a change in acceleration

Can humans also perceive jounce or any higher order derivative of position? I'm trying to understand if it is actually possible or, if not, it is impossible due to human limitations?

Thanks in advance
 
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  • #2
To think about this you need to consider how the body gives the sense of those things. i.e. what does it feel like.

For instance - we do not "feel" our velocity by noting the change in position so much as from the wind in our faces and the vibration/sensation of movement.
The relative positions of things around us provide a clue though, especially for low speeds where the sense is sometimes fooled by small motions in the surrounding objects.

We feel accelerations as a pressure or a push, similar to gravity.
Motion simulators exploit this by tilting the simulator to simulate horizontal acceleration.
As before - visual cues reinforce this sensation (the simulator will also play a movie of an accelerating POV).

So what would a low continuous jerk feel like? - remember that this is the technical term not the common use word.
Well... it would feel like the direction and/or strength of gravity is slowly changing, but at a constant rate.
You'd probably spot that if you were looking for it, though you may interpret it as something else, like being slowly tilted back in your seat or as some viscous fluid impeding your limbs, depending of the visual cues.
Usually you can tell when you've made a transition between low and high acceleration though - especially if it is sudden.

You should be able to continue the reasoning to higher orders.
 
  • #3
Simon Bridge said:
To think about this you need to consider how the body gives the sense of those things. i.e. what does it feel like.

For instance - we do not "feel" our velocity by noting the change in position so much as from the wind in our faces and the vibration/sensation of movement.
The relative positions of things around us provide a clue though, especially for low speeds where the sense is sometimes fooled by small motions in the surrounding objects.

We feel accelerations as a pressure or a push, similar to gravity.
Motion simulators exploit this by tilting the simulator to simulate horizontal acceleration.
As before - visual cues reinforce this sensation (the simulator will also play a movie of an accelerating POV).

So what would a low continuous jerk feel like? - remember that this is the technical term not the common use word.
Well... it would feel like the direction and/or strength of gravity is slowly changing, but at a constant rate.
You'd probably spot that if you were looking for it, though you may interpret it as something else, like being slowly tilted back in your seat or as some viscous fluid impeding your limbs, depending of the visual cues.
Usually you can tell when you've made a transition between low and high acceleration though - especially if it is sudden.

You should be able to continue the reasoning to higher orders.

But there must still be a limit to how many derivatives we can perceive or take into account in our reasoning/thinking, because we are limited. Do we rely mostly on position, velocity and acceleration and consider a constant jerk to simplify things?
 
  • #4
That is correct: there are many limits on our abilities.
You can continue the reasoning provided to discover where the limit lies in this case.

Do we rely mostly on position, velocity and acceleration and consider a constant jerk to simplify things?
It is difficult to know what you are asking here.

We rely on our sense of jerk (i.e. and for want of a better term) every day - almost every change in our motion involves non-constant accelerations.
Thus we are evolved to unconsciously account for a lot of non-linear processes: it is where a lot of our intuitions about motion come from.

The term "jerk" refers to a mathematical concept - invented to make thinking about motion easier, and easier to talk about... so it is a simplification in that sense.

When we do physics, as opposed to just walking down the street, we ask ourselves what is the least we need to know about something to still know everything about it.
The theory which gives the largest description with the least input is considered "simpler". This is why Newtonian Gravitation is simpler than Ptolemies Epicycles - they both work, but Newton's approach requires less foreknowledge and is more general.

Position, velocity, and acceleration (usually by way of forces), are all we need to know everything about the classical motion of a body.

These things are the simplification that our senses can only get through a more complicated series of impressions.

The bottom line is, in your work, you should "rely on" whatever it is that needs the least maths, and still gets you the right answer.
 
  • #5
for your response.

I can confirm that humans are capable of perceiving jounce, also known as snap, which is the fourth derivative of position. However, our ability to perceive jounce may be limited due to our sensory capabilities and processing abilities. Our brains may not be able to accurately interpret and differentiate between small changes in higher order derivatives of position. Additionally, our perception of jounce may also be affected by external factors such as distractions or limitations in our measurement tools. Therefore, while it is possible for humans to perceive jounce, it may not always be accurate or reliable. Further research and experimentation may be needed to fully understand our ability to perceive higher order derivatives of position.
 

What is position and how can we perceive it?

Position refers to the location of an object in space. We can perceive it through our sense of sight and touch. For example, we can see the position of a book on a table or feel the position of our hand on a doorknob.

How is velocity related to position and how do we perceive it?

Velocity is the rate of change of an object's position over time. It is closely related to position, as it describes how an object's position is changing. We can perceive velocity through our sense of sight, as we can see objects moving at different speeds, and our sense of touch, as we can feel the change in position when riding in a moving vehicle.

What is acceleration and how do we perceive it?

Acceleration is the rate of change of an object's velocity over time. It describes how an object's speed or direction is changing. We can perceive acceleration through our sense of sight, as we can see objects speeding up or slowing down, and our sense of touch, as we can feel the change in speed when riding in a car that is accelerating or decelerating.

What is jerk and how can we perceive it?

Jerk is the rate of change of an object's acceleration over time. It describes how an object's acceleration is changing. We can perceive jerk through our sense of sight, as we can see objects jolting or moving in a jerky manner, and our sense of touch, as we can feel sudden changes in acceleration when riding in a vehicle.

How are position, velocity, acceleration, and jerk measured and calculated?

Position, velocity, acceleration, and jerk are all measured and calculated using mathematical equations and formulas. They can also be measured using tools and instruments such as rulers, speedometers, accelerometers, and motion sensors. Scientists and engineers use these measurements to study and understand the motion of objects in the world around us.

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