The current leads the supply voltage in a series RLC circuit has its frequency _________ the resonant frequency.a)Aboveb)Belowc)Equal tod)Cannot be determinedCorrect answer is option 'B'. Can you explain this answer?

Question

Answer

The current leads the voltage in a series RLC circuit when the supply voltage is less than the resonant voltage.

Answer

The capacitive reactance is inversely proportional to frequency, for inductor it's directly proportional. so when frequency below  resonance frequency circuits acts as capacitive..

Answer

Introduction:
In a series RLC circuit, the current flowing through the circuit is determined by the applied voltage and the impedance of the circuit. The impedance of the circuit changes with the frequency of the applied voltage. At the resonant frequency, the impedance of the circuit is minimum, resulting in the maximum current.

Explanation:
When the frequency of the applied voltage in a series RLC circuit is below the resonant frequency, the reactive components (inductor and capacitor) dominate the impedance. At lower frequencies, the inductive reactance (XL) is higher than the capacitive reactance (XC), resulting in a net inductive impedance. This causes the current to lag the applied voltage.

When the frequency is above the resonant frequency, the capacitive reactance (XC) dominates the impedance. At higher frequencies, the capacitive reactance decreases, resulting in a net capacitive impedance. This causes the current to lead the applied voltage.

Reasoning:
In a series RLC circuit, the resonant frequency is the frequency at which the inductive reactance is equal to the capacitive reactance. At this frequency, the impedance of the circuit is purely resistive and minimum. The current is determined by the resistance in the circuit.

If the frequency is below the resonant frequency, the inductive reactance is higher than the capacitive reactance. This results in a net inductive impedance, causing the current to lag the applied voltage.

If the frequency is above the resonant frequency, the capacitive reactance is lower than the inductive reactance. This results in a net capacitive impedance, causing the current to lead the applied voltage.

Therefore, the current leads the supply voltage in a series RLC circuit when the frequency is above the resonant frequency.

Conclusion:
The current in a series RLC circuit leads the supply voltage when the frequency is above the resonant frequency. At frequencies below the resonant frequency, the current lags the supply voltage. The resonant frequency is the frequency at which the inductive reactance is equal to the capacitive reactance, resulting in a purely resistive impedance.

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