Im not sure if I should be trying to use this equation
adj^2 + opp^2 = hyp^2 ?
I really am stumped that you don't know where along the string the bead is.
Homework Statement
A 100 g bead is free to slide along an 80 cm long piece of string ABC. The ends of the string are attached to a vertical pole at A and C, which are 40 cm apart. When the pole is rotated about its axis, AB becomes horizontal.
Homework Equations
F = ma...