|MadSci Network: Physics|
Absolutely! A car uses electricity for many of it's functions, and electric currents produce magnetic fields. A car's starter motor uses about 100 amps for a couple of seconds (that's what the car battery is for) and during normal running it uses a few amps. You may be able to detect the magnetic fields with an inexpensive compass. Hold the compass a few feet from a parked car while someone starts it. The magnetic field should deflect the needle. The fields produced by a running car engine are smaller, but they should be detectable if you get close enough (pop the hood and hold the compass next to the engine. If you're young, ONLY try this with the help of an ADULT!). Of course, the metal body of the car may have a magnetic field of its own, so you'll have to test whether the field changes when the car is turned off.
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