Copper and Chromel Wire Segments

Apparatus consisting of a strand of different segments of wire

Concept Overview:

1. Different materials will produce a different amount of heat due to differing resistance, even if the current through the materials is the same.

Lecturer Procedure

Step(s) to Follow	Expected Result
1. Turn on DC Switch 2. After about 10 seconds, the NiCr segments will begin to glow. 3. Pinch the copper segments with your hand 4. (optional) place paper over the NiCr wire segments 5. (optional) measure the voltage drop over each segement of wire.	3 - You will be able to touch the copper segments, since they are still cool 4 - The paper will catch fire (students enjoy watching this) 5 - There will be a different voltage drop due to the differing resistances of the materials (Ohm's Law)

Step(s) to Follow

Expected Result

1. Turn on DC Switch

2. After about 10 seconds, the NiCr segments will begin to glow.

3. Pinch the copper segments with your hand

4. (optional) place paper over the NiCr wire segments

5. (optional) measure the voltage drop over each segement of wire.

3 - You will be able to touch the copper segments, since they are still cool

4 - The paper will catch fire (students enjoy watching this)

5 - There will be a different voltage drop due to the differing resistances of the materials (Ohm's Law)