The pendulum bob in the above figure must circle the rod interrupting its swing, and the string must remain taut at the top of the swing. How far up must the bob be raised before releasing it to accomplish these goals?
I don't know where to begin with this because I don't quite understand what i'm supposed to find.. I've tried finding Ep and Ek using 1/2mv2=mgh but i don't seem to have enough info.
Thank you in advance for any suggestions.