# science

Suppose an ideal car jack has an input work 2750 J. It lifts a car 0.35 meters in 8 seconds.

a. What is the output work of the jack?
b. How much power is required to lift the car?
c. What is the efficiency of the jack?

I can't give a answer because I am very confused.

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1. a. An ideal jack: Work output = Work input = 2750 J.

b P = Work/t = 2750J./8s.= 344 J/s = 344 Watts.

c. Efficiency = Po/Pi = 344/344 = 1.0 = 100 %.

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