If it'll make you feel better I had b44's '90's song "get down" stuck in my head. So whenever I encountered a problem I just imagined the physics paper getting 'down on me'... can't get worse than that. DO NOT LISTEN to '90's music before an exam, please DOONNNT!!
I was expecting two 9 markers, maybe that’s why. The actual nine marker provided also had a calculation element to it so it withdrew on the theory a bit. I just feel it was easier, because I hate waffling about theory, I prefer actual mathematical analysis.
I was going to mention tension, however I didn't because I felt it was unecessary to the net forces, because a component of the centripetal force really is a manifestation of the tension in the string. Although, the oblique linear force (net force) is due to tension.
Hang on... that can't be right actually @Qiaochu Chen, I saw the dot point book had a pretty much identical question, and they obtained the same result as using \tan\theta=\dfrac{v^2}{rg}. Did they do it wrong as well? I'm confused now.
@Qiaochu Chen this is how I did it.
By resolving forces, we see that the centripetal force points inwards, and the bead experiences a downward acceleration.
\tan\theta=\dfrac{F_c}{F_g}
\tan\theta=\dfrac{\left(\dfrac{mv^2}{r}\right)}{mg}
\tan\theta=\dfrac{v^2}{rg}...