Date: Fri, 26 Apr 2002 08:41:57 -0500

Author: Thomas Senior

Subject: Re: Wire for Slide Wire Pot.

Post:

Nichrome wire is available from Sargent-Welch, and other science supply companies, for a price.

I used a meter + length taped to a meter stick for students to measure the resistance as a function of length. I have also shown the length needed to get enough current to glow red hot with 12 volts, then ask how long it needs to be for 120 Volts. Of course i cheat by using a variac. It does not offer any isolation from dangerous voltages, but when the students see the device, it discourages them from
doing the demo at home with any old wire they might find.

Tom



Those who can, do.
Those who understand, teach.

Tom Senior
Physics Teacher 847-784-6739
New Trier High School
385 Winnetka Ave
Winnetka, IL 60093

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