Physics

Problem

An elevator motor lifts

20

passengers, each of average mass

60\,\text{kg}

, to a floor

15\,\text{m}

above the starting level in

25\,\text{s}

. If the motor operates with an efficiency of

80\%

, calculate the input power supplied to the motor. (Take

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