Verifying Stokes' theorem (orientation?)

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SUMMARY

This discussion focuses on verifying Stokes' theorem for the vector field F = over the hemisphere defined by x² + y² + z² = 1, y ≥ 0. The user successfully completed the surface integral but encountered confusion regarding the correct parametrization for the line integral. The proposed parametrization r(t) = was identified as having the wrong orientation. The correct orientation should follow the right-hand rule, which dictates that the parametrization must align with the positive y-axis and maintain a counterclockwise direction when viewed from above.

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  • Understanding of Stokes' theorem and its applications.
  • Familiarity with vector fields and surface integrals.
  • Knowledge of parametrization techniques in multivariable calculus.
  • Ability to apply the right-hand rule for orientation in vector calculus.
NEXT STEPS
  • Review the correct application of Stokes' theorem in various contexts.
  • Study the right-hand rule and its implications for vector field orientation.
  • Learn about different parametrization methods for curves on surfaces.
  • Explore examples of verifying Stokes' theorem with different vector fields and surfaces.
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Students and educators in multivariable calculus, particularly those studying vector calculus and applications of Stokes' theorem. This discussion is beneficial for anyone seeking to clarify concepts of orientation and parametrization in relation to surface integrals and line integrals.

Feodalherren
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Homework Statement


F= <y,z,x>
S is the hemisphere x^2 + y^2 + z^2 = 1, y ≥ 0, oriented in the direction of the positive y-axis.
Verify Stokes' theorem.

Homework Equations


The Attempt at a Solution


So I completed the surface integral part. I'm trying to do the line integral part of Stokes' theorem and end up with the same answer.
Where I get confused is there parametrization part.

I said that r(t) = <cos t, 0, sin t>, 0≤t≤2∏.
Apparently that's the wrong orientation. But when I "grab" the y-axis with my thumb in the positive y-direction and curl my fingers they go from the z axis to the x-axis counter clockwise. Isn't that the CORRECT orientation?
I guess what I'm asking is how do I determine the orientation when I'm using Stokes' theorem. I assume I want the same counter clockwise orientation that I do for Green's theorem.
 
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Your parameterization goes in the opposite direction. As t goes from 0 to pi/2, r(t) goes from <1, 0, 0> to <0, 0, 1> — in other words, from the x-axis to the z-axis.
 
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