A 320-G Mass and a 400-G Mass Are Attached to the Two

Multiple Choice

A 320-g mass and a 400-g mass are attached to the two ends of a string that goes over a pulley with a radius of 8.70 cm. Because of friction, the pulley does not begin to rotate. What is the magnitude of the frictional torque on the bearing of the pulley if the system is in static equilibrium?

A) 0.00683 Nm
B) 0.614 Nm
C) 0.0787 Nm
D) 0.0626 Nm
E) 0.000696 Nm