Alright this is the problem, i hope i describe it so you can all understand it(adsbygoogle = window.adsbygoogle || []).push({});

You start out holding the bob at and angle of 90 degrees (horizontal), with the string tight. Then release the bob, when the angle hits 0 degrees a fixed rod is placed somewhere between the top of the string and the bob. This cuts the lenght of the pendulum so that the pendulum now spins around the fixed rod

At what spot on the string should the fixed rod be placed that will allow the bob to spin all the way around the fixed rod at least once

By doing guess and check i concluded that it would be at exactly half way down the string to allow it to spin around the fixed rod

But i cant figure out how you would figure it out

i kno you use mg sin theta to find the PE i believe but i cant figure out what to do from there

If you dont get my description i can prolly make a video to show what i mean

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# Homework Help: Pendulum Problem with a twist

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