The voltage gain of a tuned amplifier is maximum at resonant frequency.
A tuned amplifier is a type of amplifier that is designed to amplify signals at a specific frequency. The resonant frequency of a tuned amplifier is the frequency at which the amplifier has the maximum gain. The gain of an amplifier is the ratio of the output voltage to the input voltage.
The gain of a tuned amplifier is determined by the inductance and capacitance of the tuned circuit. The inductance and capacitance of the tuned circuit are chosen so that the resonant frequency of the tuned circuit is equal to the desired frequency of amplification.
When the input signal is at the resonant frequency of the tuned circuit, the impedance of the tuned circuit is minimum. This means that the current through the tuned circuit is maximum. The maximum current through the tuned circuit causes the maximum voltage across the tuned circuit. This maximum voltage is amplified by the amplifier and the output voltage is maximum.
When the input signal is not at the resonant frequency of the tuned circuit, the impedance of the tuned circuit is not minimum. This means that the current through the tuned circuit is not maximum. The current through the tuned circuit causes a voltage across the tuned circuit that is not maximum. This voltage is amplified by the amplifier and the output voltage is not maximum.
Therefore, the voltage gain of a tuned amplifier is maximum at resonant frequency.