An LC circuit is an electric circuit consisting of an inductor (L) and a capacitor (C), used primarily for oscillations and filtering.
What causes oscillations in an LC circuit?
Oscillations in an LC circuit are caused by the interchange of energy between the electric field in the capacitor and the magnetic field in the inductor.
What is resonance in an LC circuit?
Resonance in an LC circuit occurs when the circuit's natural frequency matches the frequency of an external source, resulting in maximum energy transfer.
How is the resonant frequency of an LC circuit calculated?
The resonant frequency is calculated using the formula f = 1/(2π√(LC)), where L is the inductance and C is the capacitance.
What role does damping play in an LC circuit?
Damping reduces the amplitude of oscillations over time, usually due to resistance in the circuit, preventing perpetual oscillation.
How does a pure LC circuit differ from an LCR circuit?
A pure LC circuit excludes resistance, while an LCR circuit includes resistance (R), affecting damping and oscillation frequency.
What happens to the charge and current in an LC circuit during oscillations?
The charge on the capacitor and the current through the inductor oscillate sinusoidally and are out of phase by π/2 radians.
What is the initial condition often assumed in LC circuits for analysis?
A common initial condition is a fully charged capacitor with no initial current through the inductor.
Why are LC circuits employed in radio technology?
LC circuits are used in radio technology for tuning to specific frequencies, as they can resonate at the desired signal frequency.
What is meant by impedance in the context of an LC circuit?
Impedance is the combination of resistance and reactance (capacitive and inductive) in an AC circuit, affecting current flow.
What is the phase relationship between voltage and current in an ideal LC circuit at resonance?
At resonance, the voltage and current in an ideal LC circuit are in phase, meaning there is no phase difference.
What energy transformations occur in an LC circuit during oscillations?
Energy alternates between stored electric energy in the capacitor and stored magnetic energy in the inductor.
Can LC circuits store energy indefinitely?
In theory, an ideal LC circuit with no resistance could store energy indefinitely, but practical circuits lose energy over time due to resistance.
How does capacitor size affect resonant frequency in an LC circuit?
A larger capacitor results in a lower resonant frequency, as the resonant frequency is inversely proportional to the square root of capacitance.
What is the quality factor (Q) in an LC circuit?
The quality factor (Q) measures the sharpness of the resonance peak and is defined by the ratio of stored energy to energy dissipated per cycle.