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20 Cards in this Set
- Front
- Back
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What is a magnet?
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A magnet is the name given to an object that produces a magnetic force/field
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What is a domain?
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Domains are the millions of little magnets that accumulate to make up the larger magnet. Magnetic particles
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Is the Earth a magnet?
What is its magnetic field called? |
Yes, it is called the magnetosphere
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What is a temporary magnet?
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We can magnetise a magnetic material by rubbing a bar magnet over it in the same direction. This causes all the domains to line up in one direction. However, the magnetic effect will wear off shortly.
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What is a permanent magnet?
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A material that shows magnetic properties whilst it is in a external magnetic field. A magnet that retains its mgnetism after leaving a magnetic field. We can make permanent magnets by hitting or heating a metal to make the domains stay in line.
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Which poles attract and repel?
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Like poles repel, unlike poles attract. eg, N-N repel
N-S attract |
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How do the domains of a permanent magnet beccome demagnetised?
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A permanent magnet becomes demagnetised by hitting or heating it. This will knock the domains out of alignment.
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What is electricity?
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Electricity is built up when electrons (negative charged particles of a atom) move in a conductor (eg. metal, wire water) in a closed loop. This is also known as current.
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What is static electricity?
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Static electricity is all about charges which are not free to move. This causes them to build up in one place and it often ends witha spark or a shock when they finally do move.
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What is electrostatic force?
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An object that is charged with static electricity is said to be surrounded by a force field and can exert electrostatic force. This means it can cause other objects nearby to move because of the field.
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How do I know which materials will gain a charge?
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The types of materials that can gain a charge are called isulating materials. They don't allow negative charges to move through them.
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What happens to the built up charge?
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When objects are highly charged, a spark is produced and negative charges jump between the charged object and the metal. When this happens the insulating material is no longer charged. That is, it has returned to neutral.
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How can we give objects static electricity?
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When certain pairs of objects are rubbed together, electrons can move from one object to the other. Rubbing causes a buildup of static electricity because it increases the area of contact between the objects.
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What are the subatomic particles?
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protons, electrons, neutrons. Everything around you is made of atoms and combinations of these atoms. In the middle of each atom is a nucleus. The nucleus contains two kinds of tiny particles, called protons and neutrons. Orbiting around the nucleus are even smaller particles called electrons. Static Electricity is created when electrons move from the atoms of item to another (like hair and a comb).
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What materials are magnetic?
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Materials containing nickel, iron, cobalt.
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What does neutral mean?
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Having no charge.
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How does a compass work?
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A magnetised needle that is free to rotate always rotates towards other magnetism.
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What is an ion?
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An atom that has a positive electrical charge due to the loss of one or more electrons.
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What is a conductor?
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Other atoms have a weak bond with their electrons. Materials made from these atoms are conductors, like metal.
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What is an insulator?
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Some types of atoms hold their electrons very tightly. Materials made from these atoms are called insulators like cloth, plastic, glass and dry air.
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