| A | B |
|---|
| Magnetism | the force of attraction or repulsion of magnetic materials (p.15) |
| Magnetic pole | the ends of a magnetic object |
| Magnetic field | the region around a magnet where the magnetic force is exerted (p.17) |
| Magnetic field lines | lines that map out the magnetic field around a magnet (p.17) |
| Atom | the smallest particle of an element that has the properties of that element (p.18) |
| Element | a substance in which all the atoms are alike; one of about 100 basic materials that make up all matter (p.18) |
| Nucleus | the core at the center of every atom (p.18) |
| Protons | a positively charged particle that is part of an atoms nucleus (p.18) |
| Electron | a negatively charged particle that orbits the nucleus of an atom (p.18) |
| Magnetic domain | a region around a magnet where the magnetic force is exerted (p.19) |
| Ferromagnetic material | a material that is strongly attracted to a magnet and which can be made into a magnet (p.19) |
| Permanent magnet | a magnet made of material that keeps its magnetism (p.20) |
| Compass | a device with a magnetized needle that can spin freely and always points north |
| Magnetic declination | the angle between geographic north and the north to which a compass needle points (p.26) |
| Van Allen belts | two doughnut-shaped regions 1 |
| Solar wind | streams of electrically charged particles flowing at high speeds from the sun |
| Magnetosphere | the region of Earths magnetic field confined by the solar wind (p.27) |
| Aurora | a glowing region produced by the interaction of charged particles from the sun and atoms in the atmosphere (p.28) |
| Electric charge | a property of electrons and protons; electrons carry a negative charge |
| Electric current | the flow of electric charges through a material (p.31) |
| Electric circuit | a complete path through which electric charges can flow (p.32) |
| Conductor | a material through which electrons move freely |
| Insulator | a material through which the charges of an electric current are not able to move (p.32) |
| Resistor | a device in an electric circuit that uses electrical energy as it interferes with the flow of electric charge (p.34) |
| Resistance | the opposition to the movement of electric charges flowing through a material (p.34) |
| Superconductor | a material that has no electrical resistance (p.35) |
| Solenoid | a current-carrying coil of wire with many loops that acts as a magnet (p.39) |
| Electromagnet | a strong magnet that can be turned on and off; a solenoid with a ferromagnetic core (p.39) |
