21.2 Internal Combustion Engines
fuel cell
A device that converts the chemical energy of a fuel, such as hydrogen, into electrical energy
ethanol
A liquid fuel made from corn
piston
A plug that slides inside a cylinder of an engine
jet engine
A type of gas turbine engine that pushes a vehicle forward as hot air and exhaust are shot out the back of the engine
external combustion engine
An engine that burns fuel to create energy; its power source is outside the engine
rotary motion
Circular motion
emissions
Gases released into the air as a result of combustion
turbine
(TUR-bin) A disk or wheel that changes the energy of moving gases or liquids into rotary motion
reciprocating motion
(ree-SIP-roh-kay-ting) In an engine, up-and-down or back-and forth motion that occurs in a straight line
propellant
In transportation, a fuel mixture that causes an explosive thrust
internal combustion engine
In transportation, an engine in which the fuel is burned inside
ignition system
In transportation, an engine system that starts the fuel burning
thrust
The high pressure that pushes a jet engine forward
crankshaft
The part of an engine that changes the reciprocating motion of the pistons to the rotary motion that turns the wheels
maintenance
The process of inspecting and servicing a system on a regular basis to enable it to continue functioning properly, to extend its life, or to upgrade its capability