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SHAKE CELL PHONE CHARGERPROTOTYPE PRESENTATIONGROUP 6

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OVERVIEWNeed: A portable cell phone charger that does not require the constant

purchase of batteries or access to a fixed sort of energy.

Solution: Harnessing the electromotive force that is generated by magnetic flux

when magnets are moved within a copper coil by the walking motion of any

person. This can be done by creating a device that is small enough to fit within

a pocket or purse and would be sensitive to the movements of that person. The

device would feature some sort of track that is lined with copper coils that a

magnet would follow through the motions of everyday life. EMF that is

generated by the constantly changing magnetic flux would then be stored within

a capacitor so that it could be used as an energy source for a cell phone while

away from a fixed source of energy like an outlet.

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FARADAY’S LAW

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The natural discharge response of a capacitor (in t-domain) with:Capacitance (C), Resistance [in wires] is:

K e^(-t/RC)OR discharge rate depends on RC time constant:

Higher Capacitance/Resistance the longer it takes to discharge

We will be required to output a minimum of 4 -6 Volts through our capacitor for adequate charging.

CIRCUITRY

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ANTICIPATED CHALLENGESDetermining the most effective arrangement in terms of maximizing voltage.

Finding the strongest magnet in the shape required to operate in this arrangement.

Settling trade off between voltage and device size.

Producing enough voltage to charge a cell phone.

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