Check on a basic kinematic problem (FBD of a cabin on a Ferris wheel)

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greg_rack
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Homework Statement
Write and explain the free-body-diagram of the forces acting on a cabin of a Ferris wheel, in a uniform circular motion at the instant in which it's at the same height as the wheel's pivot point.
Relevant Equations
Standard motion equations
Hi guys,
Schermata 2021-01-29 alle 16.09.40.pnggiven the "blacker" to be the cabin under consideration,

I firstly wrote its weight force; then, my confusion started when drawing the force applied on the cabin by the structure(##F_{r}##).
I concluded it must have been both counter-acting the weight, and acting as a centripetal force... but I'm quite uncertain about it and I'd appreciate knowing if I'm correct or no.

The path I'm taking, for now, is that vertical component ##F_{ry}## must be equal to the weight, while the horizontal ##F_{rx}## to the centripetal force, resulting thus in an inclined force with respect to the standard vertical direction, pointing in the second quadrant of an ##xy## plane.

What do you think about it? Have I made any mistakes or imprecisions?
 
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greg_rack said:
Homework Statement:: Write and explain the free-body-diagram of the forces acting on a cabin of a Ferris wheel, in a uniform circular motion at the instant in which it's at the same height as the wheel's pivot point.
Relevant Equations:: Standard motion equations

Hi guys,
View attachment 277031given the "blacker" to be the cabin under consideration,

I firstly wrote its weight force; then, my confusion started when drawing the force applied on the cabin by the structure(##F_{r}##).
I concluded it must have been both counter-acting the weight, and acting as a centripetal force... but I'm quite uncertain about it and I'd appreciate knowing if I'm correct or no.

The path I'm taking, for now, is that vertical component ##F_{ry}## must be equal to the weight, while the horizontal ##F_{rx}## to the centripetal force, resulting thus in an inclined force with respect to the standard vertical direction, pointing in the second quadrant of an ##xy## plane.

What do you think about it? Have I made any mistakes or imprecisions?
That's good. As far as your wording goes, I'd say ##F_{rx}## IS the centripetal force.

When you draw ##F_r## on your diagram, make sure you get its length/direction reasonably accurate. If drawn correctly, then 'by eye' (using the parallelogram method) you should see the vector-sum of ##F_r## and weight acts horizontally.

[EDIT: typo' corrected.]
 
And if you were asked to draw the FBD for a passenger in the cabin, you would draw an arrow parallel to the one you described above with a magnitude scaled by the ratio of the passenger's mass to the cabin's mass.

And if the passenger held a box of popcorn, ##\dots## you get the picture.