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

AI Thread Summary
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
 
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