Question

How is the resonance frequency of an LC circuit calculated?

Answer 1

The resonance frequency of an LC circuit (also known as a tank circuit) can be calculated using the following formula:


res
=
1
2



f
res
    ​

=
2π
LC
    ​

1
    ​


Where:


res
f
res
    ​

 is the resonance frequency in hertz (Hz).

L is the inductance of the coil in henrys (H).

C is the capacitance of the capacitor in farads (F).

π is a mathematical constant (approximately 3.14159).

This formula indicates that the resonance frequency of an LC circuit depends on the values of the inductance and capacitance. When the circuit operates at its resonance frequency, the reactance of the inductor (


X
L
    ​

) and the reactance of the capacitor (


X
C
    ​

) cancel each other out, resulting in a purely resistive impedance and maximum current flow through the circuit.

Keep in mind that the resonance frequency is the frequency at which the circuit naturally oscillates when it's excited by an AC voltage source. This phenomenon is utilized in many applications, such as radio tuning circuits, filters, and oscillators.