# geometric meaning behind line integrals

What are some geometric meanings behind line integrals? I know if you have a curve on the xy plane and you are given a function $f(x,y)$ then the geometric meaning is a "curtain drawn" from the function (surface) to the curve below. This is a planer curve.

However what about when we just have a helix? Similarly what the geometric meaning (or explanation) for the line integral involving a vector field $F$ and a curve. $$\int_c{F\cdot ds}$$

Here is an example:

Let $c(t)= \sin{t}, \cos{t}, t$ from 0 to $2\pi$. let the vector field $F$ be defined by $$F(x,y,z)=x\hat{i} + y\hat{j} + z\hat{k}$$ Compute $\int_c{F\cdot ds}$

Any links to pdfs and other resources helping me understanding would be very helpful!

Thanks!

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