a)thicker wireb)thinner wirec)longer wired)wire with heavy insulation
Q factor X_L / R_Eff Inductive Reactance / Effective Resistance. An inductor is made of wire, but wire has resistance, so to compare two inductors at a given frequency, the Q factor is used. A component of Effective Resistance is the resistance of the wire called R_DC. There is also R_AC, but this question has nothing to do with it. Wire resistance at a fixed temperature is R ρ ? / A. So resistance R is inversely proportional to cross sectional area A. By increasing A, the effective resistance R_EFF goes down, which will increase Q factor. Answer a. Thinner wire, decreases A making R go up. Longer wire, increases X_L, but R_Eff would go up proportionally, so Q factor would not change. Wire with heavy insulation, would not change Q factor.
There are few things that affect the Q of an inductor. - Q of an inductor depends directly on the inductance. - Q depends by the conductor thickness to spacing ratio. - Q increases with an increase in the inductor outside diameter. - Q depends by frequency (skin effect) so by the second factor the answer would be a)thicker wire
