Coriolis Force in East-West Direction

Click For Summary

Discussion Overview

The discussion revolves around the application of the Coriolis force to objects traveling in the east-west direction. Participants explore the mechanics of the Coriolis effect, particularly how it operates when latitude remains constant, and the implications of this force in various contexts, including theoretical and conceptual understandings.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants question how the Coriolis force applies to objects moving east or west since latitude does not change, suggesting that the mechanics are more complex than initially perceived.
  • One participant explains that the Coriolis force is defined by the equation ##-2m(\vec \omega \times \vec v)##, indicating that the angular velocity is relevant even when moving east or west.
  • Another participant highlights that the Coriolis force is always perpendicular to the direction of movement, causing a rightward drift in the northern hemisphere.
  • Some participants argue that the Coriolis force is zero at the equator, while others challenge this assertion, suggesting that the effect is more nuanced.
  • One participant introduces the concept of a great circle, noting that while an object travels in a straight line, it follows a curved path on the Earth's surface, which may affect the Coriolis force.
  • There is a discussion about the relationship between the Coriolis force and the centripetal acceleration experienced by objects moving east-west, particularly away from the equator.
  • Some participants express confusion over the definitions and implications of angular velocity and its relation to the Coriolis force, leading to clarifications and corrections of earlier statements.
  • One participant mentions the Eötvös effect as a vertical component of the Coriolis force, adding another layer to the discussion.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the application of the Coriolis force to east-west motion, with multiple competing views and interpretations remaining throughout the discussion.

Contextual Notes

Limitations include varying interpretations of the Coriolis force's effects, dependence on definitions of angular velocity, and unresolved mathematical steps regarding the force's application in different contexts.

  • #31
pbuk said:
Ah, but if my starting point is the Earth's surface then this understanding:

is no help to me: I cannot fire a cannonball into the surface of the Earth, and an object on a rotating disc cannot move north (up).
Then start with the Earth's surface near the North Pole. It's almost like a rotating disc.
 
Earth sciences news on Phys.org
  • #32
A.T. said:
I don't think the decomposition of the Coriolis force based on the Earth surface (like done in Earth science) is relevant to the OP's question. The question can be answered using the basic definition of the Coriolis force in a rotating reference frame, which is independent of any specific surface. East-West translates to tangential movement with or against the reference frame rotation.
Yes, I do actually regret framing the question specifically about the Earth since I would have the same exact confusion with respect to an object traveling tangentially on a rotating disc.

Thank you very much to everyone for all the posts; I'm still not that clear when it comes to relating the derivations with a conceptual understanding but it sort of makes sense to me.
 
  • Like
Likes   Reactions: pbuk, PeroK and A.T.
  • #33
person123 said:
Thank you very much to everyone for all the posts; I'm still not that clear when it comes to relating the derivations with a conceptual understanding but it sort of makes sense to me.
You're welcome. The radial Coriolis force component is a common source of confusion, because the definitions of the inertial forces in a rotating frame are based on mathematical simplicity, rather than ease of intuitive conceptualization. Here my explanation from a previous thread:
A.T. said:
One intuitive way to think about the radial Coriolis force, is as a velocity dependent modification of the centrifugal force. In fact you could order the inertial force terms in a rotating frame by direction, and lump the radial Coriolis force with radial centrifugal force. But for mathematical and historical reasons we separate them as position dependent term (centrifugal) and a velocity dependent term (Coriolis).
 
Last edited:

Similar threads

  • · Replies 25 ·
Replies
25
Views
1K
  • · Replies 13 ·
Replies
13
Views
3K
  • · Replies 1 ·
Replies
1
Views
537
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 4 ·
Replies
4
Views
4K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 25 ·
Replies
25
Views
7K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
6K