The pendulum bob B has a weight of 10 lb and is released from rest in the position shown, q = 0o. Determine the tension in string BC just after the bob is released, q = 0o, and also at the instant the bob reaches point A, q = 45o. Take r = 4 ft.
1) 21.2 N
Equation of motion:
Since the bob is just being released, v = 0. Summing up the forces applied
in n direction at B we have
Kinematics: The speed
of the bob at the instant when q = 45o
can be determined using vdv = at ds.
So the tension in the string T = 21.2 N