The driveshaft of a building’s air-handling fan is turned at 300 RPM by a belt running on a 0.3-m-diameter pulley. The net force applied by the belt on the pulley is 2000 N. determine the torque applied by the belt on the pulley, in N.m, and the power transmitted, in kW.

Answer 1

torque= force*radius

power= torque*angular speed where
angular speed= 300*2PI/60 rad/sec

this will give you power in watts.

Answer 2

torque=300Nm
power=31.41 Watts

Answer 3

torque=F*D/2=2000n(0.15m)=300 N*m
Power = Torque*angular speed
=(300 N*m)(300 RPM) (2*PI/60)
=9424 W = 9.42 kW

These are the answers in the back of the text.