heating a wire

[jangheej]

I'm trying to control the temperature of a wire/steel rod in my experiment. (of various size from a simple wire to a steel rod of diameter 5mm)

In my preliminary experiment, I simply heated with alcohol lamp.
But I'm not so sure which equation to use and if Q=cmT is the right equation, how I could calculate the value Q.

I want to construct an experiment setting (with equipments available in high school level) so that I could alter the temperature of the wire as I wish.
Can you suggest some ideas??

[JaredJames]

I don't think that equation is quite what you're looking for.

Next to using some sort of thermometer, I don't think there's an easy way to control the temperature of a metal rod.

From what you've written, it seems you are just holding the rod over a flame and so temperature control isn't a realistic option without some from of thermometer.

The way I conducted a similar style setup in university was to use an oven at pre-set temperatures to get the rod to the required temperature. That is the only way we could accurately control it.

[AlephZero]

There is too little information to answer this. A few questions (and it's easy to think of more)...

What temperature range are you interested it?
Do you want to heat the rod or wire but leave the rest of the apparatus at room temperature, or is it OK to heat everything
Does the rod/wire have to be in air when it is heated, or would it be OK in a tank of water, or oil?
Does it have to be at a uniform temperature along its length and a constant temperature over time?

You probably have two sub-problems here: (1) heating the rod and (2) measuring its temperature.

[RocketSci5KN]

http://www.heatersplus.com/nichrome.htm

Nichrome is very useful for this, and it can be 'heated' electrically. If you want a well controlled temperature, you'd need to add some sort of temp sensor and feed this back to your electronic circuit. Make sure you understand electrical safety issues.

[Danger]

I don't know how accurately it can be regulated, but induction heating might be applicable.