1. Simple Series Circuit Quiz

Simple Series Circuit Quiz

You now have a first-order differential equation where the unknown function is the capacitor voltage. Knowing the voltage across the capacitor gives you the electrical energy stored in a capacitor.In general, the capacitor voltage is referred to as a state variable because the capacitor voltage describes the state or behavior of the circuit at any time.An easy way to remember that state variables — such as the capacitor voltage v C (t) and inductor current i L (t) — describe the present situation of the circuit is to think of your car’s position and instantaneous velocity as your car’s state variables. If you’re racing along the majestic road of Rocky Mountain National Park, your GPS position and car’s speed describe the current state of your driving.The RC series circuit is a first-order circuit because it’s described by a first-order differential equation. A circuit reduced to having a single equivalent capacitance and a single equivalent resistance is also a first-order circuit. The circuit has an applied input voltage v T (t).