Exercise · ZW-STOKES-THEOREM-003 · ★☆☆ Basic
With the same curve \(C\) as in the previous exercise, compute \(\oint_C\mathbf F\cdot d\mathbf r\) for \(\mathbf F=\langle y,z,x\rangle\).
Choose one option.
A \(\tfrac32\) B \(-\tfrac12\) C \(-3\) D \(-\tfrac32\)
Show answer
← Back to the question
Explanation \(\nabla\times\mathbf F=\langle-1,-1,-1\rangle\); its product with \(\langle1,1,1\rangle\) is \(-3\) and the projected area is \(\tfrac12\), so the result is \(-\tfrac32\).
Stokes' theorem relates the circulation of a field \(\mathbf F\) along the closed curve \(C\) bounding an oriented surface \(S\) to the flux of the curl of \(\mathbf F\) through \(S\).
\[\oint_C\mathbf F\cdot d\mathbf r=\iint_S(\nabla\times\mathbf F)\cdot d\mathbf S\]
More practice problems: stokes' theorem ZW-STOKES-THEOREM-001 Let S be the disk x^2+y^2≤1 in the plane z=0, with normal mathbf k. Compute iint_S(∇×mathbf F)· dma…ZW-STOKES-THEOREM-002 Let mathbf F=langle z,x,yrangle and C the boundary of the triangle of the plane x+y+z=1 in the firs…ZW-STOKES-THEOREM-004 Let mathbf F=langle 2xyz,\;x^2z,\;x^2yrangle. What is oint_Cmathbf F· dmathbf r over any smooth clo…ZW-STOKES-THEOREM-005 If S lies in the xy-plane with normal mathbf k and mathbf F=langle P,Q,0rangle, what does (∇×mathbf…ZW-STOKES-THEOREM-006 Let S be the hemisphere x^2+y^2+z^2=1, z≥0, with upward normal, and mathbf F=langle y,-x,0rangle. C…ZW-STOKES-THEOREM-007 If iint_S(∇×mathbf F)· dmathbf S=4 with S oriented upward, what is it after reversing the orientati…ZW-STOKES-THEOREM-008 Let C be the circle x^2+y^2=4 in the plane z=3, counterclockwise seen from above, and mathbf F=lang…ZW-STOKES-THEOREM-009 If ∇×mathbf F=mathbf 0 on all of mathbb R^3, which statement is correct?