1. Conceptual Physics Bloom High School Mr. Barry Latham, M.A.Ed

2.  Magnets can attract and repel  Like repels, unlike attracts  Forces depend on distance  Inverse square rule!  Magnetic North- on a magnets, one end seeks the strongest north pole in the region  Magnetic South- on a magnets, the other end seeks the strongest south pole in the region  Always exists in pairs of N-S, even if you break the magnet in half!

3.  Lab 93!  PhET “Magnet & Compass 2.05”

4.  Magnetic field caused by moving charges  In a magnet, the electrons are always moving  When they spin on their axis all in the same direction, they produce a magnetic field!  When they spin randomly, they don’t produce any field The Earth gets its magnetic field from spinning too!

5.  Magnetic domains- areas of a material that are either aligned or unaligned to each other  There is a degree of alignment  Non- not magnetic  Partial- weak magnet  Full- strong magnet

6.  By putting a strong magnet near a non-magnet, it can cause the domains to align!

7.  Moving charges produce a magnetic field  Section 36.3  When a current travels through a wire, a magnetic field is induced  Stronger current or more wires together  Stronger magnetic field  PhET “Magnets & Electromagnets 2.05”

8.  A static charge will not interact with a magnetic field  A moving charge will be deflected by a magnetic field, though!  Force is greatest when moving perpendicular to the field lines  Force is least when moving parallel  Magnetic field of Earth deflects most charged particles from the Sun and outer space  Aurora borealis is only seen near the poles, not the equator

11.  Just as a single charge will be deflected by a magnetic field, a wire carrying a current will be deflected  The direction of the current will dictate the direction of deflection

12.  Galvanometer  Just as a compass aligns to a magnetic field, a dial can be made to do the same thing  Ammeter  Galvanometer that measures current instead of magnetic field strength  Voltmeter  Galvanometer that measures voltage instead of magnetic field

13.  If we have an alternating current, then the magnets will spin back and forth, trying to keep up with the frequency of voltage change  http://www.youtube.com/watch?v=it_Z7NdKgmY