Lecture 28a - Magnetic Field B What produces a magnetic...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
Magnetic Field B
Background image of page 1

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

View Full DocumentRight Arrow Icon
What produces a magnetic field? Magnetic charges? B-fields are created by moving charges (currents). B-fields exert a force on moving charges . electromagnet B
Background image of page 2
Permanent magnets Atoms have moving charges. In certain materials (Fe, Ni, Co) the magnetic fields of the electrons add together to give a net magnetic field. B B B Where are the moving charges?
Background image of page 3

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

View Full DocumentRight Arrow Icon
Some magnet facts No monopoles! A permanent magnet will attract a metal like iron with either the north or south pole.
Background image of page 4
5 A permanent bar magnet is broken in half. The two pieces are interchanged, keeping their orientations fixed, as shown below. Do the pieces attract or repel? 1 2 2 1 A: Attract B: Repel C: Neither! There is no net force.
Background image of page 5

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

View Full DocumentRight Arrow Icon
Visualizing B: Magnetic Field lines show direction of B and the density of lines shows the magnitude of B. Notice closed loops
Background image of page 6
The needle of a compass is a small magnet that is free to move. The needle lines up with its N pole pointing in the direction of B http://phet.colorado.edu/en/simula tion/magnet-and-compass
Background image of page 7

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

View Full DocumentRight Arrow Icon
Visualizing B: Iron filings act like tiny compass needles
Background image of page 8
If we bring a magnet near a charged sphere, will there be a force between them? A. Yes, they will attract B. Yes, they will repel C. No, there is no force
Background image of page 9

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

View Full DocumentRight Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/05/2011 for the course PHYS 220B taught by Professor Preminger during the Fall '10 term at CSU Northridge.

Page1 / 28

Lecture 28a - Magnetic Field B What produces a magnetic...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online