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3 years ago

A constant force F=47i+30j moves an object along a vector D=13i-8j. find the work done

Mathematics

2 answers:

Nikitich [7]3 years ago

3 0

$W=(47\,\mathbf i+30\,\mathbf j)\cdot(13\,\mathbf i-8\,\mathbf j)=371$

WINSTONCH [101]3 years ago

3 0

Answer: The correct answer is 371 J.

Step-by-step explanation:

The expression for work done in terms of force and displacement is as follows;

W=F.D

Here, F is the applied force and D is the displacement.

Here, the work done is equal to the dot product of force and displacement. The dot product of i.i=j.j=k.k=1.

Calculate the work done.

W=F.D

Put F=47i+30j and D=13i-8j.

W=(47i+30j).(13i-8j)

W=611-240

W= 371 J

Therefore, the work done is 371 J.

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