WEBVTT - How can an electric toothbrush recharge its batteries?

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<v Speaker 1>Welcome to Brainstuff from house stuff works dot com where

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<v Speaker 1>smart happens. Hi'm Marshall Brain with today's question, how can

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<v Speaker 1>an electric toothbrush recharge its batteries when there are no

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<v Speaker 1>metal contacts between the toothbrush and the recharging base. If

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<v Speaker 1>you own an electric toothbrush, there's a good chance that

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<v Speaker 1>it has a completely sealed toothbrush unit. The toothbrush rests

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<v Speaker 1>on the charger without any metal contacts to connect the

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<v Speaker 1>toothbrush to the base. This has the great advantage of

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<v Speaker 1>allowing the toothbrush to be completely sealed so that water

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<v Speaker 1>can't enter through those exposed contacts. It also avoids any

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<v Speaker 1>problems with water getting into the contacts and shorting out

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<v Speaker 1>the charger. This sort of sealed arrangement is called inductive charging. Essentially,

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<v Speaker 1>the toothbrush and the base form a two part transformer,

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<v Speaker 1>with the base having one part of the transformer and

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<v Speaker 1>the toothbrush having the other. When you slide the toothbrush

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<v Speaker 1>onto that base, the complete transformer is created and charge

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<v Speaker 1>can flow to the batteries. The base contains one of

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<v Speaker 1>the coils of the transformer and the metal bar the

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<v Speaker 1>toothbrush contains the second coil. When you drop the toothbrush

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<v Speaker 1>onto the base, you create the complete transformer. Do you

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<v Speaker 1>have any ideas or suggestions for this podcast? If so,

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<v Speaker 1>please send me an email at podcast at how stuff

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