lecture19

# lecture19 - Physics 2102 Gabriela Gonzlez Physics 2102...

This preview shows pages 1–5. Sign up to view the full content.

Physics 2102 Faraday’s law Physics 2102 Gabriela González

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
dA Faraday’s Law A magnetic field can create a en electrical current too! If we define magnetic flux, similar to definition of electric flux, but for an open surface with an edge: B n dt d EMF B Φ - = = Φ S B dA n B Take note of the MINUS sign!! The induced EMF acts in such a way that it OPPOSES the change in magnetic flux (“Lenz’s Law”). Then a time varying magnetic FLUX creates an induced EMF, and thus an electrical current if the edge is a wire!:
Example When the N pole approaches the loop, the flux “into” the loop (“downwards”) increases The loop can “oppose” this change if a current were to flow clockwise, hence creating a magnetic flux “upwards.” So, the induced EMF is in a direction that makes a current flow clockwise. If the N pole moves AWAY, the flux “downwards” DECREASES, so the loop has a counter clockwise current!

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Faraday’s law: Eddy Currents A non-magnetic (e.g.
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 11/18/2011 for the course PHYSICS 2102 taught by Professor Dowling during the Fall '10 term at LSU.

### Page1 / 11

lecture19 - Physics 2102 Gabriela Gonzlez Physics 2102...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online