Inductive Current Help | Andrew's Physics 2114 E&M Exam

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Andrew is preparing for his E&M final and is struggling with a problem related to inductive currents. He understands that a changing current in a long straight wire induces a magnetic field in a nearby circuit, using the equation B=(μ)(I)/(2π)(y). However, he is confused about the self-induction of the circuit and whether to ignore it, as he believes the induced magnetic fields may cancel each other out. The discussion emphasizes the importance of understanding both the external magnetic field and the circuit's self-induction effects. Clarifying these concepts is crucial for solving the problem accurately.
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Hi, I finally registered after finding help from this very useful forum for a while.

I am reviewing for my 2114 E&M Final right now and I'm looking at a sample final from last semester our professor posted:

http://www.physicscourses.okstate.edu/summy/phys2114/Documents/PHYS1214_%20Exam3_2009.pdf

Problem 2 is giving me some trouble. I have an answer that is possibly right I am just having trouble confirming my understandings of it conceptually.

So.
The long straight wire's changing current is going to induce a magnetic field on the circuit.
and I used the equation

B=(u)(I)/(2pi)(y)
Then I realized the circuit is going to induce its own magnetic field... But that magnetic field will just cancel out because the current flowing through it end up canceling out because they go in opposite directions.

Do I just ignore the circuits self-induction??

Much thanks,
Andrew
 
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