Flux - simple integral computation

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SUMMARY

The discussion centers on calculating the flux of a uniform electric field through a surface with a given area vector. The area vector A is defined as 2i + 3j, and the electric field E is given as 4i. The flux Φ is computed using the equation Φ = E · A, resulting in a value of 8 flux units. The participants clarify that since the electric field is uniform and the area vector is constant, the dot product can be directly applied without needing to integrate over dA.

PREREQUISITES
  • Understanding of vector calculus
  • Familiarity with electric field concepts
  • Knowledge of dot product operations
  • Basic principles of surface integrals
NEXT STEPS
  • Study vector calculus applications in electromagnetism
  • Learn about surface integrals in physics
  • Explore the properties of uniform electric fields
  • Review the mathematical foundations of dot products
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Students in physics or engineering, educators teaching electromagnetism, and anyone interested in understanding electric flux calculations.

quantum13
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Homework Statement


A surface has the area vector A = 2i + 3j. What is the flux of a uniform electric field through it if the field is E = 4i?

2. Homework Equations
Integral calculus, vectors

The Attempt at a Solution


I don't understand why one could do this. The integral is of E and dA, not E and A. How can I use A to determine dA?

This is a crackpot way I thought of

[tex]\Phi = \int \vec{E} \cdot \vec{dA}[/tex]

[tex] \Phi = \vec{E} \cdot \int \vec{dA} [/tex]

[tex] \Phi = \vec{E} \cdot \vec{A} [/tex]

Then Phi = 4i dot (2i + 3j) = 8 flux units

This seems like wild fantasy though as I don't know if I can pull out a constant from a dot product integral
 
Physics news on Phys.org
There is no dA to speak of. You are given A which is the same everywhere and E which is uniform. Just take the dot product as you have in your third equation. There isn't much to this problem/
 

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