Given is a 6' long 40 lb bar hung horizontally by a pin O at its end. It is released from its horizontal position and hits a stopper after reaching a 30 degree angle with the horizontal position at which it started. I am asked to find the value x for which the angular velocity is a maximum and also the corresponding angular acceleration alpha(adsbygoogle = window.adsbygoogle || []).push({});

Sum of the torques about O=I(alpha)

a(t)=r*alpha

I honestly do not know where to start with this one. do I start by summing moments about O?

Thanks in advance for any help.

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# Homework Help: Finding a max angular acceleration

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