Mechanical Problem - Find Solution Here

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In the attachment is my problem.
Thanks
 
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  • Diagram of a dark blue bar hung by two red vertical strings labelled string 1 and string 2, with a 0.5 metres marker along the right part of the bar and a white dot marked center of mass below the bar.
    Problem.PNG
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I don't think the bar will be in circular motion. The motion is rather complex since the string 1 is involved. And what is theta anyway? You haven't defined it yet.
 
First of all, this question is not homework, Unknowingly was moved to this section!

I don't think the bar will be in circular motion. The motion is rather complex since the string 1 is involved. And what is theta anyway? You haven't defined it yet.

Thanks for reply
Suppose string 1 is a solid and fixed bar; not a string actually :D, and on which the blue bar can freely rotate.

As for theta, as I said, it's how many degrees the blue bar rotates after string 1 is cut, in other words, it's the angle between the negative x-axis and the blue bar.
 
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  • Diagram of a blue bar hanging below the horizontal axis, rotated from the negative x-axis, with a red loop marking the angle labelled 'here is theta' and a note 'the blue bar after time t'.
    11.PNG
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Use the law of energy conservation to find the relationship between angle theta and angular velocity, and then compute the integral to find angle theta w.r.t. time t. The integral is hard to compute, so use wolframalpha (http://integrals.wolfram.com/index.jsp) or any other tool. I believe the result won't look nice at all.