Understanding the Confusion in Stoke's Theorem Formulas

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The discussion focuses on the confusion surrounding the application of Stoke's theorem, particularly the difference between line integrals of scalar and vector fields. The user notes that their text presents the line integral as F(C(t))*C'(t) for vector fields, while they expected it to be F(C(t))*||C'(T)||. Clarification is sought on why the latter is not used in the context of Stoke's theorem, which relates the line integral of a surface's boundary to the surface integral of the curl of a vector field. Additionally, the distinction between scalar and vector functions is explained, with scalar functions yielding a single value and vector functions producing a vector at each point. This clarification helps resolve the user's confusion regarding the formulas.
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Homework Statement



Hello, this isn't a specific problem but a part I am confused about in Stoke's theorem. In my text the section on Line integrals (if C(t) is the parameterization of the curve) as the integral of F(C(t))*C'(t) but for vector fields the formula becomes the integral of F(C(t))*||C'(T)|| now I understand this but when I got to Stoke's theorem it says The line integral of the boundary of a surface is equal to the surface integral of the curl vector. However In every example I have seen in my text the F is a vector field so I figured that the line integral should be defined as the integral of F(C(t))*||C'(T)|| but it is the integral of F(C(t))*C'(t) can anyone clear this up for me please if you don't understand my question please ask I will try to reword it more clearly! Thanks!

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physstudent1 said:
Hello, this isn't a specific problem but a part I am confused about in Stoke's theorem. In my text the section on Line integrals (if C(t) is the parameterization of the curve) as the integral of F(C(t))*C'(t)
Ok so this is for general line integrals of vector functions.

but for vector fields the formula becomes the integral of F(C(t))*||C'(T)||
This is the formula for line integrals of scalar fields, not vector fields.

However In every example I have seen in my text the F is a vector field so I figured that the line integral should be defined as the integral of F(C(t))*||C'(T)|| but it is the integral of F(C(t))*C'(t) can anyone clear this up for me please if you don't understand my question please ask I will try to reword it more clearly! Thanks!
As above.
 
thanks a lot for clearing this up

one more thing, just exactly how could I tell the differnece between a scalar function and a vector function?
 
Eg.
A scalar function of 3 variables gives you a single (scalar) value f(x,y,z) = x + y + z for every point (x,y,z).

A vector function of 3 variables gives you a vector: \mathbf{F}(x,y,z) = x \mathbf{i} + y\mathbf{j} + z\mathbf{k} for every point (x,y,z)
 
oh that makes sense thanks the other definitions I found online I couldn't really understand but this clears it up well.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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