Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
In parallel resonance impedance is
Minimum
Maximum
Both of these
None of these
Maximum
In a parallel resonance circuit (tank circuit) consisting of an inductor and a capacitor in parallel, the impedance offered to the source is at its maximum value. At resonance, the inductive susceptance equals the capacitive susceptance, resulting in a minimum current drawn from the supply for a given voltage.
In a parallel resonance circuit (tank circuit) consisting of an inductor and a capacitor in parallel, the impedance offered to the source is at its maximum value. At resonance, the inductive susceptance equals the capacitive susceptance, resulting in a minimum current drawn from the supply for a given voltage.
ZresтАЛ=RCLтАЛ тАФ Dynamic impedance of a practical parallel resonant circuit
frтАЛ=2╧А1тАЛLC1тАЛтИТL2R2тАЛтАЛ тАФ Resonant frequency for a practical parallel circuit
At the resonant frequency, the inductive reactance (XLтАЛ=2╧АfL) and capacitive reactance (XCтАЛ=2╧АfC1тАЛ) are equal in magnitude but opposite in phase. Consequently, the net reactive current cancels out, leaving only the resistive component (if present) or resulting in an open-circuit state in an ideal scenario. Since Z=IVтАЛ and the line current is minimized, the impedance Z must be at its maximum.
Parallel resonance is also known as anti-resonance.
At resonance, the power factor of the circuit is unity (purely resistive).
The circuit draws minimum current from the source at the resonant frequency.
The impedance is purely resistive and reaches its maximum value.
Used in band-pass filter designs for high selectivity.
Essential for radio frequency tuning circuits.
High impedance can cause voltage surges in power systems.
Sensitivity to changes in component values (Q-factor dependence).
Tuned circuits in radio and TV receivers.
Induction heating equipment.
For an ideal LC parallel circuit (R=0), the impedance at resonance becomes infinite.
Option A (Minimum) is correct for Series Resonance, where the circuit behaves as a pure short circuit (excluding R).
B is correct тАФ In parallel resonance, the line current is at a minimum, which corresponds to maximum impedance across the parallel branch.
Always remember the mnemonic: Series = Minimum Z (low impedance), Parallel = Maximum Z (high impedance) at resonance.