Physics
posted by Jacie .
A 900W motor is used to lift 275.51kg of bricks a distance of 30, to the roof of the building.
a. If the motor ran for 90s how much work did it do?
b. What is the potential energy of the bricks?
I know how the calculate work, but I'm really confused about how to calculate it with the time and 900W motor.
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