1. The problem statement, all variables and given/known data I'm involved in a dispute about conical pendulums, and my friend, for whatever reason, doesn't want to believe me until somebody backs me up. Assume t is the angle that the string makes with the horizontal. 2. Relevant equations F=ma 3. The attempt at a solution Tsint = mg Tcost = mw^2*r = mw^2*Lcos(t) T=mw^2*L, where L is the length of the string Dividing gives: sin t = g/(w^2*L) This implies that if w^2*L is smaller than the acceleration of gravity, a conical pendulum cannot maintain a constant angle t with the horizontal. P.S. this is actually not a homework question. I'm almost certain my calculations are right, but my friend insists that there's no minimum rotation speed for a conical pendulum.