Find the minimum velocity for bucket in circular motion

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To determine the minimum velocity for a bucket of water in vertical circular motion, the key is to equate the gravitational force acting on the bucket with the centripetal force required to keep the water from spilling. At the top of the circle, the gravitational force must be sufficient to provide the necessary centripetal acceleration. The relevant equation involves setting the gravitational force (mg) equal to the centripetal force (mv^2/r). By substituting the radius of the circle and the acceleration due to gravity into the equation, the minimum velocity can be calculated. Understanding these forces and their relationship is crucial for solving the problem.
Tui
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Hey, first of all I'm not looking for the answer I just want a nudge in the right direction :)

Homework Statement


"a bucket of water is rotated in a vertical circle of radius 1.00m. What is the buckets minimum speed at the top of the circle if no water is to spill out?


Homework Equations


I'm not really sure where to start so.. :|


The Attempt at a Solution



I figure I must find the size of the force pulling the bucket downwards and equate that with the one pushing the water against the bucket? (I realize I've probably stuffed some force up here. this is confusing for me :))

If anyone could help with the equations I need then I can hopefully work this out on my own. Thanks a lot in advance
 
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Hey could it be that a(centrefugal or whatever :P) = v^2 / r

So I put -9.8 in for acceleration and work out v?
 
We need to pull the water to make it rotate or centripetal force
Since at the top the gravity is pulling the water down.

If mg=mv^/2, the resultant force is just to keep it rotating and not going anywhere else.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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