2. Bell work

3. Magnetism from Electricity IAN pg 9-7

4. Electromagnetism  Electric current running through wires produce a magnetic field  Electromagnetism is the interaction between electricity and magnetism  Electric current in a wire isn’t a strong magnet.

5. Solenoid  A solenoid is a current carrying wire coiled.  It is stronger than just a current carrying wire.  To increase it’s magnetic strength  Add more loops of wire  Increase the current

6. Electromagnet  An electromagnet is a solenoid with an iron core.  This is the strongest magnet, because the iron core’s domains align. Can be 110x stronger than a solenoid with the same # of loops.  Increase strength  Add loops  Increase current  Bigger iron core

7. Magnetic force and Electric current  Electric current in a wire creates a magnetic field that can exert a force on magnets-moving them.  The direction of the magnetic field depends on the direction of the current that is produced.  Also Magnets can move current carrying wires!

8. Uses of Electromagnets Electromagnetisms are particularly useful because they can be turned on and off as needed and they are used for heavy lifting. Electromagnets attract objects containing iron only when a current exists in the wire. When there is no currents in the wire, the electromagnetism is turned off. Electromagnetisms are particularly useful because they can be turned on and off as needed and they are used for heavy lifting. Electromagnets attract objects containing iron only when a current exists in the wire. When there is no currents in the wire, the electromagnetism is turned off.

9. DOORBELL This is how the doorbell works as the arrows show the steps from the previous slide.

10.  An electric motor is a device that converts electrical energy into kinetic energy.  All electric motors have an armature-a loop or coil that can rotate.  This is placed in between a permeate magnet or electromagnet.  In motors that have direct current a device called a commutator is attached to the armature to reverse the direction of the electric current in a wire.

11.  A commutator is a ring that is split in half and connected to the ends of the armature.  Electric current enters the armature through brushes that touch the commutator.  Every time the armature and the commutator make a half-turn, the direction of the current reverses.

13. Magnet lab You will need a sheet of notebook paper

14. Pg 3-4 in Lab book  Use the stick, string, magnets and cup.  See what they can do.  Make sure you can untie knots!  Return all supplies to their original condition.

15.  Put all supplies back into the cup!  What did you discover?  How can magnets be used?  Draw 3 pictures of what you did.

16. Pg 7-9  Keep the washers in the trays until you use them.  Use one magnet. How many did it hold? Draw it on your graph.  Use 2 magnets How many? Graph it.  Use 3 magnets-How many? Graph it.  Use 4 magnets-How many? Graph it.

17.  Put all supplies back into the tray!  Write down how many washers each # of magnets held.  Look at your graph…how many do you think 6 magnets will hold?  12 magnets?  Why do you think this?