Rotation and centrifugal force

Click For Summary

Discussion Overview

The discussion revolves around the nature of centrifugal force from the perspective of a rotating observer, exploring whether rotation is relative like linear motion. It includes theoretical considerations and interpretations of rotation in the context of physics, particularly in relation to Einstein's theories.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant questions the cause of centrifugal force from the perspective of a rotating observer and whether rotation is relative.
  • Another participant asserts that centrifugal force is not a true force and is merely a product of mass and acceleration, agreeing that rotation is relative like linear motion.
  • A different viewpoint claims that rotation can be determined unambiguously without reference to other frames, citing tools like a gimbaled gyroscope or a ring interferometer.
  • One participant suggests that considering rotation as absolute is easier, proposing a model where the universe is stationary and discussing implications from Einstein's General Relativity, although noting that this perspective may not be practical.

Areas of Agreement / Disagreement

Participants express differing views on whether rotation is relative or absolute, with some asserting it is relative while others argue for an absolute perspective. The discussion remains unresolved with multiple competing views present.

Contextual Notes

There are limitations in the discussion regarding the definitions of rotation and centrifugal force, as well as the assumptions made about the nature of the universe and reference frames. Some mathematical steps and implications of Einstein's theories are not fully explored.

member 529879
what is the cause of the centrifugal force from the perspective of the rotating observer? Also is rotation relative like linear motion?
 
Physics news on Phys.org
Centrifugal force is never actually a force (it has no 3rd law reaction). It is always a mass x acceleration term.

Yes, rotation is relative like linear motion.
 
OldEngr63 said:
Yes, rotation is relative like linear motion.
Rotation is not relative. You can unambiguously determine how fast a reference frame is rotating without reference to any other frame. For example, you can use a gimbaled gyroscope or a ring interferometer.
 
It's easiest to consider rotation to be absolute by considering the universe to be stationary. But Einstein did not like that any coordinate system was preferred over another. Consider the example of a person on a merry-go-round. Einstein's General Relativity Theory allows us to consider the entire universe to be rotating around a stationary merry-go-round. His theory creates a distortion of space that pulls objects away from the center of the merry-go-round. (I believe this has only been calculated with a greatly simplified model of the universe.) This is very satisfying theoretically, but it is not a practical way of looking at rotation.
 

Similar threads

Undergrad G-force centrifuge mounted on opposite rotating platform
  • · Replies 4 ·
Replies
4
Views
1K
Undergrad How Does Centrifugal Force Affect Objects on a Rotating Disk?
  • · Replies 18 ·
Replies
18
Views
3K
High School Centrifugal Force on Rotating 4" tire / wheel @ 100mph
  • · Replies 15 ·
Replies
15
Views
3K
Undergrad Remark on centrifugal force in Heino Falcke's black hole book
  • · Replies 22 ·
Replies
22
Views
3K
Undergrad Centrifugal forces don't exist in reality?
  • · Replies 93 ·
4
Replies
93
Views
8K
Undergrad Difference between centrifugal force vs reactive centrifugal force?
  • · Replies 78 ·
3
Replies
78
Views
6K
Undergrad Why Does a Glass Move Outward When Opening the Fridge Door?
  • · Replies 154 ·
6
Replies
154
Views
9K
High School Centrifugal force spinning Basketball
  • · Replies 1 ·
Replies
1
Views
1K
Graduate Centrifugal Force Experienced at the Earth's North Pole
  • · Replies 24 ·
Replies
24
Views
5K
Undergrad Centrifugal Effects During Rail Launch
  • · Replies 3 ·
Replies
3
Views
1K