Vertical Component Reactions given angular velocity

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The discussion focuses on calculating the vertical component reactions at pin O of a pendulum consisting of a disk and a rod, specifically when the pendulum is horizontal with an angular velocity of 8 rad/s. Key parameters include the mass of the disk (15 kg), the radius (0.25 m), and gravitational acceleration (9.81 m/s²). The moment of inertia for both the rod and disk is calculated, but the user struggles to incorporate angular velocity into their solution. Suggestions include considering the centripetal acceleration and summing forces from gravity and centripetal effects. The conversation highlights the complexities of dynamics problems involving rotational motion and forces.
SteliosVas
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Homework Statement



A pendulum consists of a disk of mass M1, and a slender rod of M2 (which happens to be 0kg),.

Determine the components of reaction that the pin O, exerts on the rod just as it passes the horizontal postion, at which time its angular velocity is ω.

Know we know M1 = 15kg
a which is radius of disk is 0.25m
Rod is 1m
=8rads/s
g= 9.81m/s2

Homework Equations



Well

I of rod=1/12 ML^2
I of disk=1/4 MR^2+ 1/12 ML^2
I=Icom + Mh^2
T=2pi sqrt(I/Mgh)

Now i don't know how I can fit in the angular velocity into this..

The Attempt at a Solution



Well I tried taking the moment from point O, and got 15*9.81 = 147.15N.
I got the moment of inertia = 23.67kgm^2

After that I am lost :(

I have attached a picture, if that might help.

THese problems are taking out of my dynamics textbook :/
 

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Hi!

I would assume it has to do something to do with the mass of the pendulum and the centripetal acceleration that the disk has due to its rotation. The force due to the rotation would be m*Omega^2*r. What about summing the force due to gravity and the one due to the centripetal acceleration? I hope this helps.
 

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