Angular Momentum tricky problem

AI Thread Summary
The discussion revolves around a challenging homework problem related to angular momentum, where the poster expresses confusion and difficulty in applying the relevant equations. They mention using the parallel axis theorem and attempt to calculate the mass moment of inertia but acknowledge neglecting frictional torque and the angle in their solution. The feedback emphasizes the need for complete calculations to understand the approach taken. The poster seeks guidance on how to tackle similar problems in the future. Clarity in showing work is essential for effective assistance in solving physics problems.
lecammm
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Homework Statement


As the picture shows, we are given several variables, but I am near completely lost. I am behind in my course and am trying to catch up as best as I can but this problem is really hard for me


Homework Equations



The equations that I have used are;

parallel axis theorem
angular acceleration = tangential acceleration*radius

The Attempt at a Solution


I know that this solution will be completely wrong as I haven't utilised the frictional torque, nor the angle.

So, by applying the parallel axis theorem for the mass moment of inertia;

I0 = I + mr^2
I(slender bar) = 1/12 * m * L^2
∴ I0 = 1/12 * m * L^2 + mr^2

then used the fact that:

ƩM0 = I0:

and therefore:

mgb = I0 * angular acceleration:
where b is the distance from the COM

however, as assumed, this gave the wrong answer, I'm really stuck with it and I want to know how I can do it for problems to come. Thanks! :D
 

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You need to show your calculations.

Your equation for the sum of the moments = I0 is incomplete.

How are we to know what you've done if you don't provide your work?
 
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