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Author Topic: Can a Faraday torch charge without being shaken?  (Read 2229 times)

John

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Can a Faraday torch charge without being shaken?
« on: 27/11/2010 12:30:12 »
John asked the Naked Scientists:
   
Can a Faraday flash-light self charge without shaking?

What do you think?
« Last Edit: 27/11/2010 12:30:12 by _system »


 

Offline RD

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Can a Faraday torch charge without being shaken?
« Reply #1 on: 27/11/2010 12:57:43 »
Can a Faraday flash-light self charge without shaking?

Maybe if you put it next to an alternating magnetic field, say on top of a mains transformer.

[this would be like those rechargable toothbrushes which charge via an induction loop in the base]   
« Last Edit: 27/11/2010 12:59:23 by RD »
 

Offline CliffordK

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Can a Faraday torch charge without being shaken?
« Reply #2 on: 29/11/2010 11:43:49 »
Do you have one?

I had one once.  I wasn't too impressed.

It came with a small battery so it would seem to work in the store.  But, once the battery died, one had to shake the light constantly.  And, of course, the battery was dead before I bought it.  Ever try doing car repairs while shaking your flashlight back and forth with one hand?

Anyway, the flashlight will presumably work for a period of time without shaking it, as long as the battery is good.
Many batteries will spontaneously recover slightly between discharges.

Obviously any kind of a battery charger would also work with it such as a solar cell, or even a "wall wart" if you got it wired up properly.

As RD mentioned, anything that produces an alternating magnetic field may also activate the generator.  Perhaps permanent magnets mounted on a windmill?

You could build a teeter-totter, perhaps activated by dripping water, or some mechanical device.
 

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Can a Faraday torch charge without being shaken?
« Reply #2 on: 29/11/2010 11:43:49 »

 

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