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clairez93

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## Homework Statement

1. A cylindrical gasoline tank 3 feet in diameter and 4 feet long is carried on hte back of a truck and is used to fuel tractors. The axis of the tank is horizontal. Find the work done in pumping the entire contents of the fuel tank into a tract if the opening on the tractor tank is 5 feet above the top of the tank in the truck. Gasoline weighs 42 pounds per cubic foot.

2. Consider a 15-foot chain hanging from a winch 15 feet above ground level. Find the work done by the winch in winding up the specified amount of chain, if the chain weighs 3 pounds per foot.

## Homework Equations

## The Attempt at a Solution

1. I visualized it as being chopped into little chunks of rectangles:

dW = dF * x

dF = (weight)

weight = 42*4*1.5*dh

dF = 42*4*1.5*dy * (5-y)

[tex]\int^{3}_{0}42*4*1.5*dy * (5-y)[/tex] = 2646

Book Answer: 2457pi

2. dW = dF * x

dF = 3 dy

d = 10-y

[tex]\int^{10}_{0}3*(10-y) dy[/tex] = 150

Book answer: 300

Can anyone help me see my mistakes?