Finding the Angle of a Bar PQ using Geometry and Theta

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To find the angle of bar PQ, the discussion emphasizes using geometric principles rather than relying solely on complex equations involving angular acceleration. The participant suggests that since point OQ moves with constant angular velocity, the angular acceleration might be zero, but acknowledges that this could lead to bar PQ experiencing acceleration due to changing theta. There is confusion about the applicability of the mentioned equation for angular motion. Ultimately, the recommendation is to apply basic geometry to determine the angle of bar PQ as a function of theta. This approach simplifies the problem and avoids complications with angular acceleration calculations.
whitejac
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Homework Statement


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Homework Equations


I want to say I should be using this one:
aA = aB + α x rA/B + ω x (ω x rA/B)

The Attempt at a Solution


The only problem is that if I'm supposed to find the angular acceleration then i'd have to take the... inverse of the cross product? To get it back and I don't think that that's possible. I also want to say that it's zero because OQ moves with constant angular velocity, but I believe that that would result in PQ moving with acceleration because theta would be changing?
 
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I don't think that equation will help.
Just use a bit of geometry to find the angle of the bar PQ as a function of theta.
 
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