The term spark ignition is used to describe the system with which the air-fuel mixture inside the combustion chamber of an internal combustion engine is ignited by a spark.
It is a process that uses an electrical field induced in a magneto or coil. The field builds to many thousands of volts and then is collapsed via a timed circuit. The resulting surge of current travels along a wire and terminates at the spark plug inside the combustion chamber. An electrical spark occurs as the charge tries to jump the precision gap at the tip of the spark plug at exactly the moment a precisely metered mixture of fuel and air has been thoroughly compressed in the combustion chamber. The resulting controlled explosion delivers the power to turn the reciprocating mass inside the engine.
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