Understanding Basic Electrical Concepts and Circuits
The Atom
The atom is the basic unit of matter. It consists of a nucleus containing protons and neutrons, around which electrons revolve. Electrons carry a negative charge, while protons carry a positive charge. Neutrons and other particles have their own charges.
Electric Charge
Electric charge is a fundamental property of matter responsible for electrical phenomena. The continuous displacement of electrons is called electric current.
Conductive and Insulating Materials
Conductive materials allow the passage of electric current, while insulating materials do not.
Electrical Circuits
An electrical circuit is a set of interconnected elements through which an electric current circulates. A generator, such as a battery, alternator, dynamo, solar photovoltaic cell, or hydrogen cell, provides the energy needed to move electrons. Generators have two poles, one positive and one negative, typically connected by a copper or aluminum conductor.
Electrical Receivers
Electrical receivers convert electrical energy into other useful forms of energy.
Control and Protection Devices
Control devices allow for the direction and manipulation of electric current, enabling it to be stopped or started at will. Protective devices interrupt the current when it becomes excessively high.
Electrical Diagrams
An electrical diagram is a graphical representation using symbols to depict the elements within a circuit.
Circuit Connections
Circuit elements can be connected in two ways:
- Series: Elements are connected one after another, so the output of one element is the input of the next.
- Parallel: Each element is connected in a shunt, so all elements have the same input and output.
Effects of Electric Current
Electric currents cause various effects on the elements they pass through, transforming into other types of energy:
- Heat: When electrons collide with atoms in a material, some of their energy is converted into heat. Components used to produce heat are called resistors.
- Light: When a material is heated by an electric current, it can begin to emit light, a phenomenon known as incandescence.
- Movement: The conversion of electrical energy into motion is achieved through electric motors.
Electrical Burden
Electrical burden refers to the amount of electricity stored in a body.
Basic Electrical Quantities
- Voltage (V): Indicates the electrical potential difference between two points in a circuit, measured in volts (V).
- Current Intensity (I): Represents the amount of electrons passing through a given point in the circuit per second, measured in amperes (A).
- Resistance (R): Describes the opposition to the flow of electric current within a circuit, measured in ohms (Ω).
Measuring Instruments
- Voltmeter: Measures electrical voltage, with scales in volts or millivolts.
- Polarimeter (Tester): Used for various electrical measurements across different scales.
- Ammeter: Measures current intensity, with scales in amperes or milliamperes.