Line Integral Homework: Solving Problems with W = F*dr and Pictures

In summary, the conversation is about a homework problem involving the equation W = F*dr and the attempt at solving it, with the person asking for help with parts b and c. The other person suggests using line equations and trigonometric functions to describe the paths and also points out a mistake in the integration direction for part a).
  • #1
Erbil
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0

Homework Statement



Given by picture.

Homework Equations



W = F*dr

The Attempt at a Solution



Given by pictures.
 

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  • #2
You should really say what your question about the problem is. And providing less blurry snapshots would really help. If the question is 'where did I go wrong' it looks to me like it's at the very end. Try and find it. You have a much clearer view of your work than I do.
 
  • #3
Ok.You're right.I will try to fix my fault.But I don't have any idea about b and c? Can you help me for b and c?
 
  • #4
Erbil said:
Ok.You're right.I will try to fix my fault.But I don't have any idea about b and c? Can you help me for b and c?

c is just two straight line paths. What's a line equation for each part? And if you want a circular path it's probably easiest to use trig functions to describe it. Can you give a parametric form for the circle using cos and sin? BTW I think you are also integrating backward in part a). You want to go from (1,0) to (0,1), not the other way around.
 
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FAQ: Line Integral Homework: Solving Problems with W = F*dr and Pictures

What is a line integral?

A line integral is a mathematical tool used to calculate the total value of a vector field along a specific path. It is represented by the formula W = F * dr, where W is the line integral, F is the vector field, and dr is the infinitesimal change in position along the path.

How is a line integral calculated?

A line integral is calculated by breaking down the path into small segments and finding the dot product of the vector field and the infinitesimal change in position along each segment. The sum of these dot products over the entire path gives the total value of the line integral.

What is the significance of the direction of the path in a line integral?

The direction of the path is important in a line integral because it determines the sign of the dot product between the vector field and the infinitesimal change in position. This sign affects the overall value of the line integral and can change the result significantly.

Can line integrals be calculated in higher dimensions?

Yes, line integrals can be calculated in higher dimensions. In fact, the formula for a line integral can be extended to n-dimensional spaces, where n is any positive integer. The concept of a path remains the same, but the calculation becomes more complex as the number of dimensions increases.

How can line integrals be represented visually?

Line integrals can be represented visually by drawing a curve that represents the path and arrows that represent the vector field at different points along the path. The direction and length of the arrows indicate the magnitude and direction of the vector field, while the curve shows the path along which the line integral is being calculated.

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