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Let F = (5xy,7y²) be a vector field in the plane, and C the path y = 4x² , joining (0,0) to (1,4) in the plane.

Evaluate ∫c F.dr

User Ficuscr
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1 Answer

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The work done by the force field F along path C, parametrized by y = 4x² from (0,0) to (1,4), is 5 Joules.

To evaluate the line integral ∫c F.dr along the path y = 4x² from (0,0) to (1,4), we substitute y with 4x² and dy with 8x dx.

The vector field F = (5xy,7y²) becomes (20x³,112x´) after substitution.

Consequently:

∫c F.dr = ∫0¹ (20x³ dx, 112x´ dx).⋅dr

The work done along path C is a scalar, so we calculate the dot product of F with dr (dx, 0):

W = ∫0¹ 20x³ dx = 20 ∫0¹ x³ dx = 20 [x´/4] from 0 to 1 = 20 [1´/4 - 0´/4] = 5 Joules.

User Marty Cortez
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