- #1
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Dear all,
there is something bugging me for a while now, and it's about a favourite topic of confusion: the Coriolis-force!
A fictitious force is a force which disappears if you transform to an inertial frame. At the algebraic level I have a good understanding of this, I think (Newton's 2nd law not being covariant under time-dependent rotations). Now my conceptual confusion is this: if I see those lovely satellite photos with those curly atmospheric movements like
it is often stated that this rotation is due to the Coriolis force: winds are being deflected due to the rotation of the Earth in going from high to low pressure. But somehow I can't reconcile this with the statement that a fictitious force disappears if you become inertial. This would mean that if I would hang in outer space, inertial "with respect to the stars", this lovely hurricane would stop rotating in front of my eyes, and winds would simply go straight from high to low pressure without deflection. Where do I go wrong here?
Let's make a comparison to the Foucault pendulum:
From the inertial point of view outside of earth, the Earth is rotating underneath the pendulum, while on Earth (where we stand still with respect to the earth) we see the pendulum's plane rotating (precessing). Of course, in both case the pillars are kicked. Somehow, I don't see something similar happening for our hurricane, as in "it stops to rotate for an inertial observer hanging outside of the earth".
So what's my silly thought here? Thanks in advance! ;)
there is something bugging me for a while now, and it's about a favourite topic of confusion: the Coriolis-force!
A fictitious force is a force which disappears if you transform to an inertial frame. At the algebraic level I have a good understanding of this, I think (Newton's 2nd law not being covariant under time-dependent rotations). Now my conceptual confusion is this: if I see those lovely satellite photos with those curly atmospheric movements like
it is often stated that this rotation is due to the Coriolis force: winds are being deflected due to the rotation of the Earth in going from high to low pressure. But somehow I can't reconcile this with the statement that a fictitious force disappears if you become inertial. This would mean that if I would hang in outer space, inertial "with respect to the stars", this lovely hurricane would stop rotating in front of my eyes, and winds would simply go straight from high to low pressure without deflection. Where do I go wrong here?
Let's make a comparison to the Foucault pendulum:
From the inertial point of view outside of earth, the Earth is rotating underneath the pendulum, while on Earth (where we stand still with respect to the earth) we see the pendulum's plane rotating (precessing). Of course, in both case the pillars are kicked. Somehow, I don't see something similar happening for our hurricane, as in "it stops to rotate for an inertial observer hanging outside of the earth".
So what's my silly thought here? Thanks in advance! ;)