Question

Problem 6.28 You bring a boat toward the dock by pulling on a rope with a force of 100 newtons through a distance of 7 meters. How much work do you do? (Include the appropriate sign.) joules Then you slow the boat down by pushing against it with a force of 50 newtons, opposite to the boat's movement of 4 meters. How much work do you do? (Include the appropriate sign.) joules What is the total amount of work that you do? joules the tolerance is +/-596

Answer 1

Solution)

We know,

Work done is given by,

W = Fscos(theta)

Part a)

W1 = 100*7*cos(0) = + 700 J (Ans)

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Part b)

W2 = 50*4*cos(180) = -200 J (Ans)

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Part c)

Total work,

W = W1 +W2 = 700-200 =500 J (Ans)

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