# Inductive Current Help

1. May 1, 2010

### BurnieMac

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 [Broken]

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

Last edited by a moderator: May 4, 2017
2. May 1, 2010

### BurnieMac

Close this thread as well