Spinning a bucket in a vertical circle

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proace360
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Homework Statement


You swing a 6.5 kg bucket of water in a vertical circle of radius 1.2 m.
(a) What speed must the bucket have if it is to complete the circle without spilling any water?

m=6.5
r=1.2


Homework Equations


maybe f=ma
f=m(v^2/r)

The Attempt at a Solution


What I did was set fc=6.5(V^2)/1.2, and since f=ma, I had a (or v/t)=V^2/1.2. I end up with the equation 1.2vt, which just brings me in circles. What can I do?
 
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proace360 said:

Homework Statement


You swing a 6.5 kg bucket of water in a vertical circle of radius 1.2 m.
(a) What speed must the bucket have if it is to complete the circle without spilling any water?

m=6.5
r=1.2


Homework Equations


maybe f=ma
f=m(v^2/r)

The Attempt at a Solution


What I did was set fc=6.5(V^2)/1.2, and since f=ma, I had a (or v/t)=V^2/1.2. I end up with the equation 1.2vt, which just brings me in circles. What can I do?

First of all think about where the greatest challenge to keep the water in the bucket will be.

What condition must be met for the water to stay in the bucket and not come out?
 
Remember that the equation f = (mV^2)/r is a condition that must be satisfied for centrifugal force; it is not a law.