Before I start posting videos, let’s begin studying electrical circuits with an introduction to an electrical quantity described in words, scientific notation, or decimal notation. We’ll then convert this quantity to an alternate description.

Also, we want to introduce three signal variables: current (i), voltage (v) and power (p) to the basic variables charge (q) and energy (w). Given these variables, we want to find the magnitude and direction (sign) of the unspecified variables.

As we mention in our earlier blog, the basic purpose of these videos is to introduce the analysis and design of linear circuits. Circuits are indeed important since electrical signals are use to carry energy and information.

We can view a circuit as an interconnection of electrical devices such as a resistor (R), inductor (L) and capacitor (C) which we will describe how these devices work later. A signal is a time-varying function and in this case a time-varying electrical quantity such as voltage and current.

Some examples include a DVD player that generates primarily audio and video signal outputs processed by electronic circuits. The electrical signal outputs from the DVD player carry energy and information.

Linear Circuits is an important property in studying circuits. If I double my input at a certain tone frequency to a circuit processing system then my output will be doubled at that same tone frequency. If I get a different tone, then the system is nonlinear. Linearity greatly simplifies the process of analyzing and designing circuits.

So let’s get started, with some symbols and units. We’ll use the international system (SI) of units. The system consists of the following fundamental units: meter (m), kilogram (kg), second (s), ampere (A), kelvin (K), and candela (cd). Using these fundamental units, other measurement units are derived.

Related posts:

- Introduction to Circuit Analysis I plan to start a series of videos on circuit...
- Solving First-Order Linear Differential Equations – RL-Series Circuit (Example 1) In this example, we will be modeling a simple RL-series...
- Solving Linear First-Order Differential Equations – RC-Series Circuit (Example 2) This is another example of modeling a simple RC-series circuit...
- Solving Linear First-Order Differential Equations – RC-Parallel Circuit (Example 4) This example models an RC parallel circuit as a first...
- Solving Linear First-Order Differential Equations – RL-Parallel Circuit (Example 3) An example showing how to model an RL-parallel circuit as...