Term
| what creates a magnetic field |
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Definition
| any charged particle in motion |
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Term
| the lines of a magnetic field are always: |
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Definition
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Term
| what can induce a magnetic field |
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Definition
| spinning electric charges |
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Term
| what are the three classifications of magnets |
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Definition
| natural, permanent, electromagnet |
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Term
| what are examples of natural magnets |
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Definition
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Term
| what is a permanent magnet |
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Definition
| artificially produced by aligning their domains in the field of an electromagnet |
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Term
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Definition
| wire wrapped around an iron core |
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Term
| how is a magnetic field created with an electromagnet |
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Definition
| when you run an electric current through the wire (the stronger the current, the stronger the magnetic field) |
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Term
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Definition
| according to the manner in which it interacts with an external magnetic field |
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Term
| what are the different ways in which matter can be classified |
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Definition
| diamagnetic, ferromagnetic, paramagnetic, and tesla |
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Term
| a coil of wire without an iron core |
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Definition
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Term
| what does electrons flowing through a wire produces |
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Definition
| a magnetic field about that wire |
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Term
| a coil of wire with an iron core |
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Definition
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Term
| what is the difference between a magnetic field produced by a bar magnet and electromagnet |
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Definition
| a magnetic field produced by an electromagnet can be adjusted or turned on and off |
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Term
| electromagnetic induction |
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Definition
| occurs when any part of a circuit is in a changing magnetic field |
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Term
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Definition
| the strength of an induced current depends on 4 factors |
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Term
| what are the 4 factors of faraday's law |
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Definition
| strength of field, velocity of field, angle of the field, and the number of turns in the conductor |
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Term
| how can a change in the magnetic field be accomplished |
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Definition
| move the magnet, move the conductor, adjust the current |
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Term
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Definition
| the induction of an opposing voltage in a single coil by its own changing magnetic field |
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Term
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Definition
| the generation of an alternating current in a secondary coil by supplying an alternating current to the primary coil |
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Term
| what are the three types of electromechanical devices |
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Definition
| electric generator, electric motor, and transformer |
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Term
| what does an electric generator do |
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Definition
| convert mechanical energy to electrical energy |
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Term
| how does a DC generator work |
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Definition
| converts mechanical energy into a direct current using a communicator ring |
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Term
| how does an AC generator work |
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Definition
| converts mechanical energy into an alternating current |
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Term
| how does an electric motor work |
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Definition
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Term
| what powers the rotating anode of an x-ray tube |
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Definition
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Term
| what does a transformer do |
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Definition
| changes the intensity of alternating voltage and current by mutual induction (only works with AC) |
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Term
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Definition
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Term
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Definition
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Term
| transformer laws effect on current |
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Definition
| Is/Ip=Np/Ns, inversly proportional |
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Term
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Definition
| turns ratio greater then 1 |
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Term
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Definition
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Term
| what are the three main causes of transformer inefficiency |
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Definition
| resistance, hysteresis, eddy currents |
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Term
| what causes resistance in a transformer |
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Definition
| the current flowing through the copper wire- results in heat generation |
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Term
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Definition
| when the alternating reversal of the magnetic field caused by the AC which causes more resistance and heat |
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Term
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Definition
| swirling currents produced by alternating magnetic fields because of AC |
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Term
| what are the three types of transformers |
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Definition
| closed core, autotransformer, and shell-life |
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Term
| what is a closed-core transformer |
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Definition
| built around a square core of ferromagnetic material made of laminated layers of iron (reduces energy loss caused by eddy currents) |
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Term
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Definition
| iron core with only one winding of wire aournd that is the primary and secondary winding (self-induction) |
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Term
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Definition
| two closed cores merged together with primary and secondary coils wound together (more efficient because the magnetic field lines are confined) |
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