Jumping Batteries Batman!

The Puzzler

TOM: I know the answer! You put the two cables together and you put the bumpers touching.

RAY: Exactly. Jumper cables consist of two wires with clamps on each end so you've got four clamps. They're kind of stuck together through the insulation, and if you peel them apart and then clamp the ends together, you have instead of one 16-foot long pair of jumper cables, you have one 32-foot long cable, but you only have one. But trucks have steel bumpers and steel frames, and the steel of the frame is the conductive path for all the electrons.

TOM: Phew.

RAY: You've made the electrons travel through one cable, and then through the frames of both vehicles to get back to the original jumping battery, and voila --
the thing was started. Who's our winner?

TOM: The winner this week is Jane Fuqua from Zionsville, Indiana, and for having her answer selected at random from among the pile of correct answers that we got, Jane is going to get a 26-dollar gift certificate to the Shameless Commerce Division at cartalk.com, with which she can get a copy of our new four-CD collection called Field Guide to the North American Wacko. These are four shows that we think will help familiarize you with the species we've identified as the not-so-rare North American Wacko.

RAY: Congratulations, Jane!

[ Car Talk Puzzler ]

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