An electric cargo winch of efficiency 75% is used to pull a load of mass 500 kg up a rough inclined plane at a constant speed of 1.5 m/s, as shown in the diagram below.
The incline makes an angle α \alpha\,α with the horizontal, where sinα=0.12\sin\alpha = 0.12sinα=0.12. The resistance to the motion of the load is a constant force of 212 N.
Assuming g=9.8 m/s2g = 9.8\text{ m/s}^2g=9.8 m/s2, what is the electrical input power required by the winch motor?
0.90 kW0.90\text{ kW}0.90 kW
1.18 kW1.18\text{ kW}1.18 kW
1.60 kW1.60\text{ kW}1.60 kW
0.75 kW0.75\text{ kW}0.75 kW