(Line integral) Compute work through vector field

In summary, the task is to compute the work done along the Archimedes spiral using the vector field F(x,y)=<cos(sin(x)+y)cos(x)+e^x, cos(sin(x)+y)+y>, which is found to be conservative by checking the equality of the partial derivatives of P and Q with respect to x and y. This allows the use of the fundamental theorem of line integrals, but difficulties arise in finding the antiderivative of Q=cos(sin(x)+y)+y with respect to x, as well as understanding the meaning and use of r=θ and polar coordinates in this problem. Further steps or approaches may be needed to solve this task.
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SiriusAboutAstronomy
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Homework Statement


"Consider the Vector field F(x,y)=<cos(sin(x)+y)cos(x)+e^x, cos(sin(x)+y)+y>. Compute the work done as you traverse the Archimedes spiral (r=θ) from (x,y)=(0,0) to (x,y)=(2∏,0). (Hint: check to see if the vector field is conservative)


Homework Equations


1) F(x,y)=<P,Q> is conservative if [itex]\partial[/itex]P/[itex]\partial[/itex]y=[itex]\partial[/itex]Q/[itex]\partial[/itex]x

2) [itex]\int[/itex][itex]_{c}[/itex][itex]\nabla[/itex]f[itex]\cdot[/itex]dr= f(r(b))-f(r(a))



The Attempt at a Solution



1) The vector field is conservative by equation one: the partial derivative of P and Q with respect to y and x, respectively, are equivalent and equal cos(x)sin(sin(x)+y)

Difficulties:
The field is conservative, which means there exists a function f with ∇f=F. So I could use the fundamental theorem of line integrals, but I don't know how to integrate Q=cos(sin(x)+y)+y with respect to x.
As opposed to this I could try to do a change of variables but I don't know where to start with that.
I think some of my trouble comes from trying to wrap my head around r=θ, does that mean that the position vector r(x,y)=θ? or does it mean that r(r,θ)=<θ,θ>? If the latter is true, do I use polar coordinates? And if I do, how do I put F(x,y) into polar coordinates if r=<θ,θ>
 
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or do I need to put F(x,y) into one variable (say theta) and how do I do that? With r(x,y)=<θ,θ>, do I just plug that into F(x,y) or do I need to find f=antiderivative(F(x,y)) and then plug in r(x,y)=<θ,θ> for x and y
 

Related to (Line integral) Compute work through vector field

1. What is a line integral?

A line integral is a type of integral used in multivariable calculus to calculate the area under a curve in a vector field. It involves integrating a function along a specific path or curve.

2. How is work computed through a vector field?

Work is computed through a vector field using a line integral. This involves calculating the dot product of the vector field and a small segment of the path or curve along which work is being done. The integral of this dot product over the entire path gives the total work done.

3. What is the significance of computing work through a vector field?

Computing work through a vector field is important in physics and engineering, as it allows us to calculate the amount of work done by a force over a given path or curve. This can be used to determine the energy and motion of objects in a system.

4. How is a line integral different from a regular integral?

A line integral is different from a regular integral in that it involves integrating a function over a specific path or curve, rather than over an interval on a single axis. This makes it a multivariable integral, requiring different techniques for computation.

5. What are some real-world applications of computing work through a vector field?

Some real-world applications of computing work through a vector field include calculating the amount of work needed to move an object through a path, determining the flow of fluids in a system, and analyzing the forces acting on an object in motion.

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