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www.NDSCSnano.com Shake Flashlight North Dakota State College of Science Applied Science and Technologies www.NDSCSnano.com
www.NDSCSnano.com
Shake Flashlight
North Dakota State College of ScienceApplied Science and Technologies
www.NDSCSnano.com
www.NDSCSnano.com
Electrical Basics
• Current is the flow of electrons• Voltage is electrical pressure• Resistance is the opposition to the flow of
electrons• Ohm’s Law: V = I x R (voltage = current x
resistance)
Closed CircuitClosed Circuit
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Basic Electrical Principle
A magnetic field is generated around a wire as current flows through it.
http://www.educypedia.be/electronics/javaelectricity.htm
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Shake Flashlight
The basic principle of "moving magnet plus coil makes electricity" is the foundation for electrical generators, so in a sense this is old technology.
http://www.msscweb.org
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Voltage Generation
When a magnet passes through a tightly-wound coil of insulated wire, a voltage is generated. As the magnet changes direction, so does the polarity of the voltage. This action generates an AC voltage.
http://www.msscweb.org
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Schematic
The AC voltage is sent to a full-wave bridge to convert the AC to a pulsating DC voltage. This energy is stored in Capacitor C1. The switch turns on the LED.
http://www.msscweb.org
http://www.play-hookey.com/ac_theory/ps_rectifiers.html
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Components
http://www.msscweb.org
Full-wave Diodes Capacitor (Battery)
