Self-resonant frequency

Okay kiddo, have you ever seen a swing set or a pendulum move back and forth? When you push the swing or the pendulum, it moves in a certain way and it keeps going back and forth at a certain speed. That speed is called its natural frequency.

Now, let's talk about something called a circuit. It's like a little pathway that lets electricity flow through it. Sometimes, in some circuits, there's something called an inductor. It's a little loop that can store energy in a magnetic field.

When you add a capacitor to the circuit along with the inductor, it starts to behave like a swing or a pendulum. The energy bounces back and forth between the capacitor and the inductor like a bouncing ball.

If you keep changing the electrical frequency going into the circuit, at some point, the capacitor and the inductor will start to vibrate at their natural frequency. That's called the self-resonant frequency.

So basically, just like how a swing has a natural speed it likes to move at, some circuits have a natural frequency at which they vibrate. That's their self-resonant frequency.