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Electricity
Taken from Quiz #1
| Question | Answer |
|---|---|
| Ability of Certain Materials to attract iron, cobalt or nickel. | Magnetism (Cobalt and Nickel have to be in their purest form) |
| What is the most common element used for magnets? | Nickel |
| Electrons spinning in prodominantly one direction create a tiny magnet refered to as | A Magnetic Dipole |
| When many of these magnetic dipoles align with each other they create an organized grouping called (use a strong magnetic field to align the dipoles) | A Magnetic Domain |
| Each atom will have a North and South pole | Dipole |
| Lines of force in space | Flux |
| Lines of force in opposing directions attract each other | Magnetic Attraction |
| Lines of the force in the same direction repel each other | Magnetic Resistance |
| First Law of Magnetism | 1. Every magnet has a North and South pole. |
| Second Law of Magnetism | 2. Like poles repel and unlike poles attract each other. |
| Third Law of Magnetism | 3. force of attraction (or repulsion) varies directly as the strength of the poles and inversely as the square law of the distace between them. (Yes, inverse square law |
| Strength of a Magnetic Field (SI Unit | tesla (T) |
| Any spinning electric charge will induce a ____________ | Magnetic Field |
| If every electric charge creates a magnetic field , why is it that everything is not magnetic? | The magnetic field will end up cancelling each other out. |
| Natural Magnets | Lodestones |
| Lodestones are found ___ ___ _______ | in the earth |
| Lodestones consists of an ________. | iron ore |
| Artificial Permanent Magnet | manufactured by magnetic induction |
| Electromagnetic | Iron bar wrapped with a wire carrying eletric current. (ONLY magnetic when electricity is flowing through it) |
| Nonmagnetic Materials | Not affected by magnetic fields (ie. glass, wood, plastic) |
| Diamagnetic Materials | Weakly repelled by magnetic fields (ie water, mercury and gold) |
| Paramagnetic Materials | Weakly attracted by magnetic fields. (ie platinum, gadolinium, aluminum) |
| Ferromagnetic Materials | Strongly attracted to magnet (ie iron, cobalt, nickel) |
| A stronger field will magnetize the material more _____ | Strongly |
| Rubbing Ferromagnetic material against a permanent magnet also helps ________. | Bring the atoms into alignment |
| Heating or dropping a magnet can ______ | Knock some of the atoms out of alignment thus weakening the magnetic field. |
| Superconducting Magnet | Used in MRI Resistance is at zero. Current still going. |