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1 year ago

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Jack and Jill are maneuvering a 3100 kg boat near a dock. Initially the boat's position is < 2, 0, 3 > m and its speed is

1.6 m/s. As the boat moves to position < 6, 0, 1 > m, Jack exerts a force of < -450, 0, 225 > N, and Jill exerts a force of < 160, 0, 320 > N.How much work Jack do? How much work Jill do?

1 answer:

AlekseyPX1 year ago

8 0

Answer:

Work Kack: -2250J

Work Jill : 0J

Explanation:

The motion began at <2,0,3>m and end at <6,0,1>m

To find the distance the boat travel is:

d'=<6-2,0-0,1-3>

d'=<4,0,-2>

Jack's work:

W=F*s

W=<-450,0,225>*<4,0,-2>

W=-1800+-450=-2250 J

Jill work:

W=<160,0,320>*<4,0,-2>

W=0

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