When measuring the resistance of a coil of wire you must realize that inductance will keep you from reading the resistance right away, Once current has stabilized you will have a pretty good reading. I did once see where a spark was generated when breaking the ohmmeter leads connected to a very large brake coil.
Your question is not too clear. As far as I know a coiled wire can not be used to find out resistance.
But if your question is about the difficulties of using a wire wound resistor in a electrical circuit experiment then you must always consider the fact that a wire wound resistor also has inductive reactance as well as resistance to any alternating current. Because of this you may measure an ac voltage across a wire wound resistor that is different from the calculated voltage if you have ignored the inductive reactance of the wire wound resistor in your calculations.
My answer is a stab in the dark and may be completely unrelated to what you are asking.
A coiled wire has inductance - the coils interact with each other magnetically - so, depending on the method used for measuring the resistance, especially if AC current flow is measured, the answer may include not only resistance but inductance. If DC current is used (as in most ohmmeters) and settling time is allowed, which happens almost automatically in large coils which settle quickly, there is no problem.
you need more detail.
You can't use a coiled wire to measure resistance.
Or do you want to measure the resistance of a coiled wire? Use an ohmmeter. No difficulties.
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