Sanity check please -- Load cable swinging outward on a rotating crane

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The discussion focuses on the physics of load cables swinging outward on a rotating crane, utilizing the equation Fcp = -m*w^2*r. Participants analyze the relationship between variables, particularly how to express r1 and r2 in terms of other parameters. There is a debate about the relevance of certain variables, with a suggestion that one variable may not be necessary. The importance of understanding the radius of rotation, R, as the sum of r1 and r2 is emphasized. The conversation concludes with a confirmation of the calculations and a light-hearted acknowledgment of simplifying the equation.
Thickmax
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Homework Statement
Please can my work be sanity checked? I think I'm on the right lines
Relevant Equations
See below
1624914062559.png
So I know

Fcp=-m*w^2*r

So from the equation -m*w^2*r=m*g*tan(theta)

r = r1+r2

so to rewrite

-m*(w^2)*(r1+r2)=m*g*tan(theta)
So
r1+r2=(m*g*tan(theta))/-m*(w^2)

r1=((m*g*tan(theta))/-m*(w^2)) - r2

Am I doing this nearly correct?
 
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Thickmax said:
Am I doing this nearly correct?
Yes, but one of your variables is not in the list of those allowed in the answer. Can you see a way to get rid of it?
 
Shouldn't ##r_2## be directly proportional to ##\omega^2##?
 
Lnewqban said:
Shouldn't ##r_2## be directly proportional to ##\omega^2##?
No the crane rotates around its base column, the radius of rotation is ##R=r_1+r_2## not just ##r_2##.
 
haruspex said:
Yes, but one of your variables is not in the list of those allowed in the answer. Can you see a way to get rid of it?
I can indeed! m's are overrated! Thank you for the confirmation
 
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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