PDA

View Full Version : Direction of induced current - VERY basic


physicsfun
Mar17-09, 12:11 AM
1. The problem statement, all variables and given/known data


A current loop with area A is placed in region II in the x-z plane, centered at the origin. (Below is a view looking down from y > 0.)

If the magnitude of the current per unit length in each sheet is increased (the directions stay the same), the induced current in the loop (looking down on the loop from the +y-axis) is:

A) in a counterclockwise direction
B) zero
C) in a clockwise direction


(picture is attached)


3. The attempt at a solution


I know this has to do with Faraday's Law, and the fact that the magnetic flux's of the current and the induced currents will be in opposite directions. However, I'm not sure if because of the orientation of the loop, if the induced current will be zero, or nonzero... or if what I just said makes any sense!!! If anyone could tell and/or explain to me what the answer is, I would greatly appreciate that.... this homework is due bright and early in the morning!

Doc Al
Mar17-09, 07:39 AM
If the magnitude of the current per unit length in each sheet is increased
Not sure what you mean by "current per unit length" or "each sheet". The diagram shows what looks like two current-carrying wires.
I know this has to do with Faraday's Law, and the fact that the magnetic flux's of the current and the induced currents will be in opposite directions.
Find the field created by those current-carrying wires. When the current increases, how does the flux through the loop change? What direction must the induced current flow to oppose that change in flux?