An electric motor is needed for a hoist. The motor is expected to provide a force of 744 lbf (337.5 kgf) at the edge of a 24-in. (61 cm) diameter pulley. The motor will run at 1200 RPM and the pulley will be attached to a gearbox to provide the correct line speed for the hoist. Assume the motor operates at 85% efficiency.
What size, hp (KW), motor should be specified for this application?
A. 170 HP (126.8)
B. 200 HP (149.1)
C. 340 HP (253.5)
D. 400 HP (298.3)
答案选B