At resonance, the LC parallel resonant circuit

Step-by-step solution

For a parallel LC circuit, the admittance is given by Y = 1 j L + j C = j ( C - 1 L ) . At resonance, the inductive reactance equals the capacitive reactance, which means C = 1 L . Substituting this into the admittance equation gives Y = 0 . Since impedance Z = 1 Y , the impedance approaches infinity as the admittance approaches zero. Therefore, at resonance, an LC parallel resonant circuit has a very high impedance. Answer: has a very high impedance.