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Magnetic Flux through a bent loop.

  1. Mar 17, 2009 #1
    1. The problem statement, all variables and given/known data
    A 10cm x 10cm square is bent at a 90deg angle as shown in the figure.

    A uniform 0.050T magnetic field points downdard at 45deg.

    What is the magnetic flux through the loop.

    2. Relevant equations

    Flux= [(Aeff)*(B)].
    Flux= [(Aeff)*(B)]*cos(theta).

    3. The attempt at a solution

    First I solved for the side due to the bend by using d= SQRT of [(a)^2*(c)^2].

    Then, I calculated the Area using A= [(d)*(b)].

    Then, I tried calculating with or without the 45deg angle using the following (which is not giving the correct answer):

    Flux= [(Aeff)*(B)].
    Flux= [(Aeff)*(B)]*cos(theta).

    Attached Files:

  2. jcsd
  3. Mar 17, 2009 #2
    Does anyone know how I am supposed to treat the bend?

    I have done problems when the area was flat, but I am not sure what I need to do differently when the area is bent. Isn't it going to decrease the area?
  4. Mar 18, 2009 #3

    Doc Al

    User Avatar

    Staff: Mentor

    Two ways to go about it:

    1) Treat it as two flat surfaces of area b*c and b*a. Find the flux through each of those surfaces and add them up.

    2) Find the surface outlined by the by the two b sides. The angled piece doesn't matter, since the field is parallel to the bend. Sure the area changes, but so does the angle that the field makes with that surface.
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