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20 Cards in this Set
- Front
- Back
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AC Generator |
Converts mechanical energy to electrical energy by utilizing the principle of electromagnetic induction. |
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DC Generator |
Convert mechanical energy into electrical energy |
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Electromagnet |
Current flowing through a coil of wire |
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Flux Lines |
Invisible lines of force surrounding a magnet |
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Magnetic Field |
Surrounds a wire when current flows through it, consists of invisible lines of force |
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Permeability |
Ability of a material to accept magnetic lines of force |
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Left Hand Rule For Coils |
Determine the polarity by grasping the coil with the left hand, with the fingers pointing in the direction of the current flow. The thumb points towards the North pole. |
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Left Hand Rule For Conductors |
Grasp with the left hand, thumb pointing in the direction of current flow, the fingers point in the direction of flux lines. |
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Electromagnetic Induction |
Occurs when a conductor passes through a magnetic field, a current is produced |
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Faradays Law |
The induced voltage in a conductor is directly proportional top the rate at which the conductor cuts the magnetic lines of force |
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Left Hand Rule For Generators |
The thumb, index finger, and middle finger are held at right angles to each other. The thumb points in the same direcrion of as the motion of the conductor, index finger points in direction of flux lines, middle finger points toward negative end of conductor, direction of current flow |
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Magnetic Induction |
The effect a magnet has on an object without physical contact. |
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Retentivity |
The ability of a material to retain its magnetic field after the magnetizing force is removed |
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Alternator |
Produces alternating current |
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Armature |
Rotating loop |
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Commutator |
Converts AC voltage to DC voltage |
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Frequency |
Number of complete cycles completed per second |
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Relay |
Electromechanical switch that opens and closes with an electromagnetic coil. As a current flows through the coil, it generates a magentic field that attracts the plunger, pulling it down. As it is pulled down, it closes the switch contacts. When the current through the coil stops, a spring pulls the armature back to the original postion and opens the switch |
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Right Hand Motor Rule |
Thumb, index, and middle finger at right angles of each other the middle points in direction of current flow in the conductor, index indicates magnetic field, thumb points in direction of motion in conductor |
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Solenoid |
A coil, when energized, pulls a plunger by a permanent magnet that is attached to a stylus (needle). The permanent magnet is placed inside a small coil. As the stylus is tracked through the groove of a record, it moves up and down and from side to side in response to the audio signal recorded. The movement of the magnet in the coil induces a small voltage that varies at the audio signal response. The induced voltage is then amplified and used to drive a loudspeaker, reproducing the audio signal. |
