# Electricity

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Free online electricity lessons for elementary school,  middle school and high school.

## Two-terminal electronic components

An electrical component can only work if it is traversed by an electric current.
It must therefore receive the electric current and then let it out.

Definition of a terminal: It is an area of an electrical component that can receive the electric current or let it out.
Comment: a terminal is also used to make connections, which means connecting an electrical component to another electrical component.

Some complex electrical components can have multiple input terminals and multiple output terminals (such as transistors or operational amplifiers).
For now we consider only simple electrical components having only one input terminal and one output terminal that are called dipole.

Definition of a two-terminal component: this is simply an electrical component that has two terminals.
Examples of dipoles: batteries, bulbs, switches so on.

 Science class Chemistry Electricity Optics Mechanics Electricity lessons Electrical components -Two-terminal electronic components - Basic electrical components - Diodes - What's a resistor ? - How to determine a resistor value ? - Resistors effects in circuits - How to use a resistor ? - Characteristic curve of a resistor How to build simple circuits and draw diagrams - How to build a basic electrical circuit - How to draw diagrams of electric circuits The electric current - Conductors and insulators - Direction of electric current in a circuit - The dangers of electricity - Current intensity - units how to measure current ? The Voltage - The voltage and its units - How to measure a voltage ? - Voltage in open and closed circuits - Rated current and voltage for a lamp Alternating voltage and current - Alternating currents effects on led - What are alternating current and voltage ? - Periodic alternating voltage and its properties - Oscilloscope - Oscillogram - Frequency - Measuring RMS voltage with a voltmeter Serie circuits - What's a serie circuit ? - Series circuit properties - Short circuit in  series circuit - Current law in series - circuits - Voltage law in series circuits Parallel circuits - What's a parallel circuit ? - Some parallel circuits properties - Short circuits in parallel circuits - Nodes and branches in parallel circuits - Current laws in parallel circuits - Voltage laws in parallel circuits Laws of electricity - Ohm's law - Current laws in series circuits - Voltage laws in series circuits - Current laws in parallel circuits - Voltage laws in parallel circuits Generating electricity - Voltage for coil wires What is an alternator ? - Alternating currents and voltages - Generating electricity in power plants Electric power and energy - Electric power and power rating - Electric power consumption by an electrical device - Relationship between - Electric power and energy