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How much work is done lifting a 35 pound object from the ground to the top of a 25 foot building if the cable used weighs 2.5 pounds per foot

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Answer:

3400 ft-lbs

Step-by-step explanation:

The Workdone in lifting the rope :

Number of feet = x

Distance = 25 feets

2.5x + 35

Taking the integral :

∫2.5x + 35 dx at x = 40

Integrating, we have :

1/2(2.5x² ) + 35x at x = 40

1/2(2.5(40)²) + 35(40)

1/2(4000) + 1400

2000 + 1400

= 3400

Hence, Workdone in lifting the rope = 3400 ft-lbs

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