Surface Integral Homework: Evaluate ∫∫σ

In summary: I can't help you with any problem if you won't tell me what you are trying to do.In summary, the problem is to evaluate a surface integral over a surface with three sides: S1, S2, and S3. S1 is a portion of a cylinder, S2 is a disk, and S3 is a portion of a plane. The homework requires the use of surface integrals and vector calculus. The student is unsure of how to start the problem and is considering using either multiple surface integrals or the divergence theorem. However, they are unsure if the divergence theorem can be used for this problem. They have not specified what they are integrating over the surface.
  • #1
Baumer8993
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Homework Statement


Evaluate ∫∫σ where S is a surface with sides S1, S2, and S3. S1 is a portion of the cylinder x2+y2 = 1 whose bottom S2 is the disk x2+y2 ≤ 1 and whose top S3 is the portion of the plane z = 1 + x that lies above S2.


Homework Equations


Surface integrals, and vector calculus.


The Attempt at a Solution


I am more stuck with starting this problem. Do I need to do two surface integrals, or something else? I am just completely lost on what to do here...
 
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  • #2
Baumer8993 said:

Homework Statement


Evaluate ∫∫σ where S is a surface with sides S1, S2, and S3. S1 is a portion of the cylinder x2+y2 = 1 whose bottom S2 is the disk x2+y2 ≤ 1 and whose top S3 is the portion of the plane z = 1 + x that lies above S2.


Homework Equations


Surface integrals, and vector calculus.


The Attempt at a Solution


I am more stuck with starting this problem. Do I need to do two surface integrals, or something else? I am just completely lost on what to do here...

What are you integrating over the surface? You can do it by integrating over the three surfaces and adding them or you might replace the surface integral with a volume integral using the divergence theorem if you just need the total over all three surfaces. Just start doing something.
 
  • #3
I though I could only use the divergence theorem for flux?
 
  • #4
Baumer8993 said:
I though I could only use the divergence theorem for flux?

Of course, if it's not a flux integral then you can't use the divergence theorem. That's why I was asking WHAT you are integrating.
 

FAQ: Surface Integral Homework: Evaluate ∫∫σ

What is a surface integral?

A surface integral is a mathematical tool used in multivariable calculus to calculate the flux of a vector field over a given surface. It involves integrating a function over a two-dimensional surface in three-dimensional space.

How do you evaluate a surface integral?

To evaluate a surface integral, you first need to parameterize the surface into a two-variable function. Then, you can use this function to set up the integral and solve it by using techniques such as substitution or partial derivatives.

What is the significance of surface integrals?

Surface integrals are important in various fields of science, such as physics, engineering, and geometry. They are used to calculate physical quantities such as electric flux, mass flow rate, and surface area.

Can you give an example of a surface integral?

Sure, an example of a surface integral is evaluating the flux of a vector field F over a surface S. The integral would be written as ∫∫S F · dS, where dS is the differential element of surface area.

What are the differences between a surface integral and a double integral?

A surface integral is a type of double integral, but it is specifically used to integrate over a two-dimensional surface. In contrast, a double integral can be used to integrate over any two-dimensional region in the xy-plane.

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