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Electrical Circuit

The Puzzler


RAY: We all know when you get into the car to start it, you put the key into the ignition, and you turn the key and electricity is directed by doing that: from the battery to the starter motor. And, of course, it makes a complete path and goes back to the battery. In fact, electrons make their migration from the negative end of the battery, into the starter motor and then back into the battery. That's how the flow of electricity takes place from the negative to the starter to the battery. Now, knowing that, if an electron were to start out at the negative terminal of the battery and you have 10 feet of battery cables and the starter motor -

TOM: Like 5 feet to the starter motor and 5 feet back.

RAY: No, I was thinking more like 4 feet to the starter and 6 feet back. How long then does it take a single electron starting at the negative battery terminal to reach the positive terminal? That is, to make the whole so-called circuit. Now, I could make this a multiple choice question, but I'm going to leave it open-ended.

TOM: Sure. I like open-ended because now, it leaves itself open to right-brained-type answers and essay-type answers.

Think you know? Drop Ray a note!

[ Car Talk Puzzler ]

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