Coriolis force - Question about sign

  • #1
Dear all

I have a question concerning the Coriolis acceleration expression. I learnt it as Ac = -2ω x v, where ω is the vector which indicates the rotation axis direction of Earth and v the velocity of a body that I want to check the Coriolis effect on.

My question: where the minus sign comes from? As far as I understand, it depends on what reference frame I use (inertial or non inertial - the minus comes from the latter, like the Earth, in my conception). Am I correct?

Thanks in advance!
 

Answers and Replies

  • #2
A.T.
Science Advisor
11,290
2,678
Dear all

I have a question concerning the Coriolis acceleration expression. I learnt it as Ac = -2ω x v, where ω is the vector which indicates the rotation axis direction of Earth and v the velocity of a body that I want to check the Coriolis effect on.

My question: where the minus sign comes from?
You can swap ω and v, and the minus sign is gone:

-2ω x v = 2v x ω

As far as I understand, it depends on what reference frame I use (inertial or non inertial
The Coriolis force exist only in non inertial frames.
 
  • #3
AlephZero
Science Advisor
Homework Helper
7,002
293
The minus sign is there because humans made the arbitrary decision to use right-handed coordinate systems rather than left handed ones.

The Coriolis force is just a consequece of Newton's laws of motion. The physics doesn't depend on what frame you use to describe it, or whether the frame is inertial or non-inertial. The details of the math depend on those things, but "the map is not the country", and similarly "the math is not the phyiscs".
 
  • #4
tiny-tim
Science Advisor
Homework Helper
25,836
251
  • #5
A.T.
Science Advisor
11,290
2,678
The minus sign is there because humans made the arbitrary decision to use right-handed coordinate systems rather than left handed ones.
To me it seems more like it's the arbitrary decision to have ω first in the term.
 

Related Threads on Coriolis force - Question about sign

Replies
39
Views
2K
Replies
8
Views
2K
  • Last Post
Replies
6
Views
707
  • Last Post
Replies
7
Views
9K
  • Last Post
Replies
7
Views
1K
  • Last Post
Replies
6
Views
6K
  • Last Post
Replies
12
Views
8K
  • Last Post
Replies
0
Views
2K
Replies
2
Views
1K
  • Last Post
Replies
3
Views
4K
Top