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Consider a force ⃗F=-x̂i+ŷj. The work done by this force in moving a particle from point A(1,0) to B(0,1) along the line segment is (all quantities are in SI units)

Asked in JEE Main 9th Jan 1st Shift 2020 · Integrating a position-dependent force

Figure: Integrating a position-dependent force
Answer: (3) 1

Step-by-step solution

W=∫⃗F· d⃗r=∫(-x dx+y dy).

Along the segment x runs from 1 to 0 and y from 0 to 1; each term integrates on its own variable.

∫₁⁰(-x) dx=[-(x²)/2]₁⁰=1/2 and ∫₀¹y dy=1/2.

W=1/2+1/2=1 J.

Why the other options are wrong

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