A lift of mass rises vertically at constant speed

PHYSICS · Multi-part · CBSE · Physics · Work, Energy and Power · Work, Energy and Power

Problem

A lift of mass

600\,\text{kg}

rises vertically at constant speed. The motor supplies

18\,\text{kW}

of power. Take

g = 9.8\,\text{m\,s}^{-2}

. (a) Calculate the speed of the lift. (b) If a frictional force of

1.2\,\text{kN}

acts downward in addition to the weight, what power would the motor need to supply to maintain the same speed?