Glossary
Capacitance (C)
Capacitance is the ability of a component, called a capacitor, to store electric charge, measured in Farads (F). It quantifies how much charge can be stored per unit of voltage.
Example:
A camera flash uses a large Capacitance (C) to quickly discharge a burst of light when the shutter button is pressed.
Circuit Analysis
Circuit analysis is the process of studying and determining the behavior of electrical circuits, including calculating values like current, voltage, and resistance at various points.
Example:
Engineers perform Circuit Analysis to design and troubleshoot electronic devices, ensuring they function correctly and safely.
Conservation of Electric Charge
This fundamental principle states that electric charge can neither be created nor destroyed, only transferred from one location to another. In circuits, this means the total charge remains constant.
Example:
When you rub a balloon on your hair, charge is transferred from your hair to the balloon, but the total amount of Conservation of Electric Charge in the system remains the same.
Current (I)
Current is the rate of flow of electric charge through a conductor, measured in Amperes (A). It represents how many coulombs of charge pass a point per second.
Example:
When you turn on a light switch, electrons begin to move through the wires, creating an electric Current (I) that illuminates the bulb.
Electrical Circuit
An electrical circuit is a closed loop or path through which electric current can flow, typically consisting of a power source, conductors, and components.
Example:
A simple flashlight contains an Electrical Circuit where a battery powers a bulb through a switch and wires.
Inductance (L)
Inductance is the property of an electrical conductor by which a change in current flowing through it induces an electromotive force (voltage) in the conductor itself or in a nearby conductor, measured in Henries (H).
Example:
The coils in an electric motor exhibit Inductance (L), which is crucial for converting electrical energy into mechanical motion.
Kirchhoff's Junction Rule
This rule states that the total current flowing into a junction (or node) in an electrical circuit must equal the total current flowing out of that junction. It is a direct application of the conservation of electric charge.
Example:
If 5 amps of current flow into a circuit junction, and 2 amps flow out through one branch, then 3 amps must flow out through the other branch, demonstrating the Kirchhoff's Junction Rule.
Ohm's Law
Ohm's Law describes the relationship between voltage, current, and resistance in a circuit, stated as V = IR (Voltage equals current times resistance).
Example:
If a circuit has a 12V battery and a 4Ω resistor, you can use Ohm's Law to calculate that 3A of current will flow through it.
Resistance (R)
Resistance is the opposition to the flow of electric current in a circuit, measured in Ohms (Ω). Materials with high resistance impede current flow more significantly.
Example:
A toaster uses a heating element with high Resistance (R) to convert electrical energy into thermal energy, toasting your bread.
Voltage (V)
Voltage, also known as potential difference, is the electric potential energy difference per unit charge between two points in a circuit, measured in Volts (V). It is the 'push' that drives current.
Example:
A 9-volt battery provides a Voltage (V) difference that can power a small electronic device.