Ah. Okay.
If velocity is constant, then acceleration of the system is 0. So the sum of the net forces should be zero. If gravity is producing a force of -800N (because gravity is going against the direction of displacement) then the motor has to produce a force of 800N. Then you could multiply...
Homework Statement
A small motor is used to operate a lift that raises a load of bricks weighing 500N to a height of 10m in 40s at constant speed. The lift weighs 300N. What is the work done by the force of the motor? What is the work done by the force of gravity?
Homework Equations
P...