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1. The problem statement, all variables and given/known data

The picture speaks for itself: one man "A" is standing of a rotating disk whose angular velocity is [tex] \omega [/tex] CCW, and another one "B" is standing still on earth. I'm riquired to find the coriolis and centrifugal forces that act on "B" as seen from "A".

3. The attempt at a solution

Coriolis:

[tex] \vec{F}_{cor} = -2m \vec{\omega} \times \vec{v}_{rel} [/tex]

Centrifugal:

[tex] \vec{F}_{cen} = -m \vec{\omega} \times (\vec{\omega} \times \vec{r}) [/tex]

where,

the angular velocity should be taken in the CW sense, since "A" sees "B" doing circles in that direction, so:

[tex] \vec{\omega}=-\omega \hat{z} [/tex]

about the relative velocity of "B" with respect to "A" i'm not quite sure because the coriolis force appears only when there's movement in a rotating frame, now "A" clearly doesn't move, but the question is: can it see "B" moving in the following velocity:

[tex] \vec{v}_{rel} = \omega r \hat{\theta} [/tex]

?!?!

and the radius vector is:

[tex] \vec{r} = R \hat{r} [/tex]

any clarification would be appreciated =)

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# Homework Help: Coriolis & Centrifugal forces

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