Posted by R on Saturday, March 23, 2013 at 11:33pm.
A ball of mass 0.750 kg is attached to the end of a 1.20m long cord that can withstand a maximum tension of 50.0 N. If swung in a vertical circle, what is the maximum velocity the ball can achieve before the string breaks?

physics  drwls, Sunday, March 24, 2013 at 6:32am
Since the circle is vertical, maximum tension is experienced when the ball is at the bottom of the loop. Tension must support both weight and centripetal force.
Require that
M*V^2/R + M*g = (maximum tension) Tmax
= 50.0 N
Then solve for V.
M*V^2/R = 50  7.35 = 42.65 N
V = sqrt(42.65*1.2/0.75)= 8.26 m/s