lecture19 - Physics 2102 Gabriela Gonzlez Physics 2102...

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

View Full Document Right Arrow Icon
Physics 2102 Faraday’s law Physics 2102 Gabriela González
Background image of page 1

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

View Full DocumentRight Arrow Icon
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!:
Background image of page 2
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!
Background image of page 3

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

View Full DocumentRight Arrow Icon
Faraday’s law: Eddy Currents A non-magnetic (e.g.
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

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 Right Arrow Icon
Ask a homework question - tutors are online