The Feeling of Accelerated Motion

Click For Summary

Discussion Overview

The discussion revolves around the perception of accelerated motion, exploring various theories including Mach's principle and the physiological responses to acceleration. Participants examine the relationship between acceleration, inertia, and the sensory experiences associated with these phenomena.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants reference Mach's principle as a theoretical framework for understanding why we feel acceleration, questioning modern scientific perspectives on this topic.
  • There is curiosity about whether the reasons behind our perception of acceleration are considered unanswered questions by proponents of various theories.
  • One participant notes that different body parts have varying inertia, which may lead to differing interactions under acceleration.
  • A question is raised regarding why acceleration is not considered relative motion and what distinguishes it between reference frames.
  • A participant introduces Newton's Bucket problem to illustrate the concept of internal sensations of rotation in the absence of external cues.
  • Another participant asserts that inertia is independent of gravitational fields, suggesting that the bucket and water would still exhibit concavity due to inertia.
  • It is proposed that accelerated motion is a result of force, and that one can perceive force even in the absence of a reference frame, linking this to the concept of inertial motion.
  • Discussion includes the physiological aspects of how humans feel forces due to compression and fluid pressure from accelerated blood flow.
  • One participant suggests that simply attributing the feeling of acceleration to inertia may overlook the complexities of Mach's principle and its implications in General Relativity.

Areas of Agreement / Disagreement

Participants express a variety of viewpoints regarding the nature of acceleration and its perception, with no clear consensus reached on the underlying theories or explanations.

Contextual Notes

Some discussions involve assumptions about the nature of inertia and reference frames, and there are unresolved questions about the implications of Mach's principle in relation to the sensation of acceleration.

nealh149
Messages
110
Reaction score
0
I've read some theories (for example Mach's principle of distant stars being the basis) of why we feel accelerated motion. What are modern sciences thoughts on this?

Couldn't it simply be collisions of particles against nerves just like the seat of a car pushes up against you in an accelerating car?
 
Physics news on Phys.org
Yeah.

I'm kind of curious about these "theories". Do the proponents of them feel that why we feel what we do is an unanswered question?
 
Yeah, that sounds like a sort of strange question. The various parts of our bodies don't have the same inertia, so they interact differently under acceleration.
 
I guess the question is why isn't acceleration relative motion, what makes it distinguishable between reference frames.
 
Maybe it's just the beer, but that last post of yours just made no sense whatsoever to me. :confused:
 
No, it's not the beer, because I'm drinking wine at the moment (in moderation of course). The OP is going to Cornell next year, which may explain the question... J/K :biggrin:
 
Well, I'm on the last of my beer, but I've still got a couple of W's Corona left, and a dozen ounces or so of tequila. Maybe by the time they're gone, I can interpret that question.
 
Sorry guys, let me try to rephrase this. I don't know if you ever heard Newton's Bucket problem, but here it goes:

If you had a water filled bucket and spin it, the water will become concave and push up against the sides of it. If you somehow suspended this bucket in empty space (a theoretical space where no other matter exists) would it still be concave. In other words, the bucket wouldn't have any external cues to measure it's rotation against, but could it still "feel" it internally?
 
Yes, because the bucket and the water have inertia. Inertia is independent of gravitational field.

Zz.
 
  • #10
Accelerated motion can only occur as a result of a force. We feel that force.

If you are way out in outer space such that you have no reference frame to give you clues, you can still tell if there is a force acting upon you. The corollary is that if you are not experiencing a force, you are not accelerating, you are in a state of inertial motion.

The bucket knows if it is experiencing a force; it is experiencing the centripetal force of the rope pulling it out of its straight-line inertial motion.
 
  • #11
Humans feel the force due to compression at the point of contact, and fluid pressure from accelerated blood.
 
  • #12
The OP appears to be asking about Mach's Principle, which attempts to explain why inertia exists and which is embodied in the mathematics of General Relativity. So answering that the reason we feel acceleration because of inertia is taking a step backward.
 

Similar threads

  • · Replies 15 ·
Replies
15
Views
4K
  • · Replies 22 ·
Replies
22
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 15 ·
Replies
15
Views
4K
  • · Replies 42 ·
2
Replies
42
Views
5K
  • · Replies 10 ·
Replies
10
Views
6K