I'll make a new thread, with the same question, but with better representation. I'll see if I can use latex because I don't know what it is. New thread coming right up
My attempt at solving case B
I've attached my attempt at case B above. What problem I'm facing is that after writing equation of angular SHM, I'm getting angular acceleration proportional to cube of angular displacement, which doesn't reduce to SHM. So how to find time period for this...