W1 Power P is the rate of doing work: P=w/t. SI unit: 1 Watt = 1 J/s a A box is being accelerated up the side of a building by a rope; a motor on the roof pulls the rope. Find the power delivered by the motor if it takes 20s to lift a 800N box 10m with a 0.1g acceleration. (Be sure to draw a picture and a FBD in your solution and use N's second law to support your answer.) b Show that P=F_vx• (Hint, substitute in the definition of work into the definition of power.)

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