Fuel Engines

• A machine is a device that changes energy from one form to another
• When the energy used by the machine is chemical energy the machine is called an engine
• Fuels store chemical energy that can be changed into heat and other forms of energy
• Engines obtain their energy from combustion of/burning up the fuel
• Engines should be as efficient as possible
• The cost of running the engine
• Its weight
• Its noise and
• Its level of pollution
• have to be kept to a minimum
• It is not possible for an engine to be 100% efficient
• This is due to losses resulting from friction as well as other factors
• Engines have cycles that they repeat and go through
• This cycles come in the form of movements that are repeated over and over again
• During the operation of a particular type of engine
• The two most popular engines in the world are the
• Petrol and
• Diesel Engines
• Each has features and cycles that are peculiar to it

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