1. Magnetism-Magnets Kailey Toro, Megan Ly, Chad Unrue, Michael Fairbanks Items 1-5 on the packet Science RULES

2. The Big Idea: A moving electric charge is surrounded by a magnetic field.

3. Magnetic Poles Each Magnet has a North and South pole Like Poles repel; Opposite poles attract BOTH poles are always present in any magnet Even when you break magnets apart, they create new North/South poles. They can create new poles even at the microscopic level!

4. Magnetic Fields The direction of the magnetic field outside a magnet is from the north to south pole When the lines are closer together, the field strength is greater The magnetic field strength is greater at the poles If we place another magnet or a small compass anywhere in the field, it’s poles will tend to line up with the magnetic field

5. Magnetic Fields A magnetic field is produced by the motion of electric charges Electric Charges Electric Forces Magnetic poles Magnetic fields There are charges surrounding the magnet, and when magnets get close together they create the magnetic field Strong magnetic field conductors: Iron, Nickel, Cobalt

6. How does a compass work?? The magnetic field around a current carrying conductor is showing by arranging compasses around a wire The compass’ line up with the magnetic field produced by the current, a pattern of concentric circles about the wire. When the current reverses direction, the compasses turn around, Showing the direction of the magnetic field changes also.

7. Earth’s Magnetic Field A compass points northwards because earth itself is one GIANT magnet. The needle in the compass aligns with the magnetic field of the earth to point you in the direction you need to know- however it DOES NOT POINT TO TRUE NORTH The discrepancy is known as the magnetic declination

8. Magnetic Field Reversals It’s been proved that Earth’s magnetic field is not stable. The poles have flip flopped throughout geological time Alternating magnetic strip of magnetized rock show that there have been times when the Earth’s magnetic field has dropped to zero and then reversed

9. Magnetic Force Equation There is always a magnetic force!!! F=qvB ▫q= amount of charge (C- for coulombs) ▫v= velocity ▫B= magnetic field ( T for teslas)

10. Right Hand Rule #1 Point fingers in direction of moving charge (q) Orient your palm so it’s facing the direction of the magnetic field (B) Extend your thumb, it’s the direction of the force This force happens only when the charge moves perpendicular to the magnetic field B

11. Right Hand Rules #2 To determine the direction of the circular magnetic field around a wire carrying a current Direct your thumb along the wire in the direction of current Your fingers curl in the direction of the circular magnetic field

12. Magnetism Problems 1. A charged particle moving in a magnetic field experiences a deflecting force that is maximum when the charge moves _________ to the field A. Parallel B. Next C. Perpendicular 2. An electromagnet can be made from a current-carrying wire coiled around a piece of: A. Iron B. Copper C. Tin D. Any metal 3. Which pole of the bar magnet is facing North? A or B?

13. Magnetism Problems 4. If you break a magnet in half… A. It will lose its magnetic pull B. Two smaller magnets will be formed C. The phenomenon varies for every type of metal used to create the magnet D. Each piece will only have one pole, not both 5. The space around a magnet, in which a magnetic force is exerted, is filled with a… A. Magnetic domain B. Iron fillings C. Magnetic Field D. nothing 6. In an electromagnet, the magnetic field intensity increases as the number of loops A. Decrease B. Increase C. No change 7. Why aren’t most materials magnetic? A. They don’t carry an electric charge B. The electric fields of the domains cancel each other out because they aren’t aligned C. Only metals can be magnetic

14. Magnetism Problems 8. Why don’t compasses point to the geographic North Pole. A. Minor imperfections in the compass B. Because of man-made magnets that are stronger than the earth’s magnetic field C. The magnetic North Pole doesn’t match the geographic North Pole 9. What causes magnetic fields? A. Moving electric charges B. Only magnetic objects can create magnets C. Static electricity 10. A Tesla is a unit of measurement of what? A. The force created by a magnetic field B. The magnitude of a magnetic field C. The electric charge of a magnet

15. Answers 1)C. Perpendicular 2) A. Iron 3) B 4) B. Two smaller magnets will be formed 5) C. Magnetic Field 6) B. Increase 7) B. The electric fields of the domains cancel each other out because they aren’t aligned 8) C. The magnetic North Pole doesn’t match the geographic North Pole 9) A. Moving electric charges 10) B. The magnitude of a magnetic field