Electricity

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What is an alternator ?

An alternator corresponds to the combination of an electric coil and a magnet which can rotate.
(At large scale, as in a power plants, the magnet is replaced by an electromagnet).

When the magnet rotates, magnetic poles approach and then move away from the coil causing the appearance of a voltage: the electric coil then acts an electrical generator.

When the magnet from an alternator (or electromagnet) rotates it has a kinetic energy which is converted into electrical energy.

An alternator therefore convert a kinetic energy into electric energy

 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