I have a quick question about a problem requiring calculating impedance of a circuit where there is no capacitor. The formula for impedance Z is Z=sqrt(R^2 + (Xl - Xc)^2). I am told capacitive reactance Xc = 0 because C = 0 (there is no capacitor in the circuit). But the formula for Xc is Xc = 1/2(pi)fC. So if C = 0, then Xc must be huge or infinite, not zero! I'm confused. Can someone please explain this contradiction to me. Thank you! P.S.: Maybe I should visualize replacing the nonexistent capacitor with a "short". A short has infinite capacitance, right???