1. how to calculate the resistance of an inductor in a circuit?for example a resistor connected series with an inductor, how to calculate the overall resistance of the inductor and resistor together?2.if inductors make induced e.m.f, why do they behave as short circuits in DC circuits3.if inductors are strong enough what don't they seem to short cicuit like in strong electromagnets?
You may be getting resistance confused with impedance. 1. But taking your question as it stands, the resistance of an inductor can only be calculated if you know the size of wire used and the length of wire. Formula is below. For total resistance of that in series with a discrete resistor, just add them together like any two resistors in series. If you mean impedance or reactance, the inductive reactance of an inductor is XL 2πfL where L is the inductance in henrys and f is the frequency. From that you can calculate the impedance: Impedance Z √(R? + X?) where X XL – Xc 2. Because DC does not induce any voltage. And they are not a short circuit, see #1 above. 3. This question makes no sense, sorry. What do you mean by strong. Resistance of a wire in Ω R ρL/A ρ is resistivity of the material in Ω-m L is length in meters A is cross-sectional area in m? A πr?, r is radius of wire in m resistivity Cu 17.2e-9 Ω-m or 17.2e-6 ohm-mm .
