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Work problem

"work" problem

1. Homework Statement
A force F(2xi+5yi)N acts on an object as it moves in the x direction from the origin to x=4.96m. Find the work W=integral vector F(dr) done by the force on the object


2. Homework Equations



3. The Attempt at a Solution

integral 0 to 4.96 (2xi+5yi)N=2x^2/2|0 to 4.96=24.6

integral 5yi=5y^2/2=5(4.96)/2=61.5

61.5+24.6=
86.1

Could someone please tell me if this is correct?

Thank you very much
 

Answers and Replies

Shooting Star
Homework Helper
1,975
4
Incorrect. There's no displacement in the y, that is, j direction.

Judging by your other posts on related topics, I would recommend another thorough reading up on this chapter.
 
Would it be like this?

Integral (2xi+5yj)(idx)|0 to 4.96=
integral 0 to 4.96(2x)dx=
2xx|0 to 4.56=
2x^2|0 to 4.56=
41.6

Work done in the y direction=0

Total work=41.6J

Thank you
 
458
0
Integral of 2x is not 2x^2. Might want to recheck that.
 
Shooting Star
Homework Helper
1,975
4
Would it be like this?

Integral (2xi+5yj)(idx)|0 to 4.96=
It's a dot product: (2xi+5yj).(idx)

integral 0 to 4.96(2x)dx=
2xx|0 to 4.56=
2x^2|0 to 4.56=
41.6
(Why did it become 4.56?)

Antiderivative of 2x is 2x^2/2.

Correct your calculation.
 

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