How do you measure the temperature of a copper wire?

Question

I'm investigating how the temperature of a wire affects the resistance. The only problem in my write-up is that I'm unsure of how to measure the temperature. I've thought about using a thermocouple, but I'm not sure how they work, or how I would connect one to a circuit. If I use one, how is this drawn in a circuit diagram?

Are there any other methods of measuring the temperature?

Thank you in advance.

Answer 1

A thermocouple would be a lousy choice; first off, it's not very sensitive; and second, it consists of two bare dissimilar wires in contact and that would short out your test wire!

I would suggest wrapping the wire around the tip of a digital meat thermometer. Use wire with a varnish coating so it's insulated electrically but not thermally; this wire is available for transformer windings and such. You'll have to strip the varnish off the endsto run a current through it, of course; sandpaper works well for that.

Wrap the wire around the tip of the probe a number of times neatly, and put a drop of glue to fasten the coil of wire to the sensor tip. When you're ready for the experiment, turn on the thermometer and measure the resistance. Heat the wire with a blow dryer and measure it again hot. Then, say, press the wire against an ice cube to measure it cold.

Answer 2

you could just use a thermometer to check the temperature .?

Answer 3

OK this is very easy! Simple trick! first set up a circuit.....  Then part of the circuit should include the copper wire...you may use crocodile clips for the connection. Immerse the copper wire in a beaker of cold water(meausure temperature of water) .....Then do the same for a higher temperature of water(say 80 or 90 C). In both set ups ....use an ammeter.This way you can find how the temperature affects resistance by comparing the ammeter reading for both set ups.