Welcome to Brainstuff from house stuff works dot com where smart happens. Hi'm Marshall Brain with today's question, how can an electric toothbrush recharge its batteries when there are no metal contacts between the toothbrush and the recharging base. If you own an electric toothbrush, there's a good chance that it has a completely sealed toothbrush unit. The toothbrush rests on the charger without any metal contacts to connect the
toothbrush to the base. This has the great advantage of allowing the toothbrush to be completely sealed so that water can't enter through those exposed contacts. It also avoids any problems with water getting into the contacts and shorting out the charger. This sort of sealed arrangement is called inductive charging. Essentially, the toothbrush and the base form a two part transformer, with the base having one part of the transformer and
the toothbrush having the other. When you slide the toothbrush onto that base, the complete transformer is created and charge can flow to the batteries. The base contains one of the coils of the transformer and the metal bar the toothbrush contains the second coil. When you drop the toothbrush onto the base, you create the complete transformer. Do you have any ideas or suggestions for this podcast? If so, please send me an email at podcast at how stuff
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