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Define i) Free air delivered (FAD) – It is volume of air delivered under the condition of temperature and pressure existing at compressor intake, i.e. volume of air delivered at surrounding air temperature & pressure. In absence of any given free air conditions these are generally taken as 1.101325 bar and 150 c. ii) Compressor capacity – It is quantity of free air actually delivered by compressor in m3 /min. iii) Swept volume – It is the volume of air taken during sanction stroke. It is expressed in m3 . iv) Pressure ratio – It is defined as delivery pressure to suction pressure.

The MPFI means multi point injection system. In this system each cylinder has number of injector to supply/ spray fuel in cylinder as compared to one injector located centrally to supply and spray fuel in case of single point injection system

Jet Propulsion: This is done by expanding the gas which is at high temperature & pressure through the nozzle so that the gas with very high velocity leaves the nozzle giving thrust in opposite direction. - Principle is based on Newton’s Second & third law of motion. Jet propulsion – Classification (1) Atmospheric jet engines (breathing engine) -Turbojet engine - Turbo prop engines - Ram jet (2) Rocket engine (Non - breathing engine)

The major air pollutants emitted by petrol & diesel engines are CO2, CO, HC, NOx, SO2, smoke & lead vapour. Effect of CO: (1) Carbon monoxide combines with hemoglobin forming carboy hemoglobin ,which reduces oxygen carrying capacity of blood. (2) This leads to laziness, exhaustion of body & headache. (3) Prolong exposure can even leads to death. (4) It also affects cardiovascular system, thereby causing heart problem Effect of CO2: Causes respiratory disorder & suffocation.

The loud pulsating noise heard within the engine cylinder is known as detonation. The following are the certain factors which causes detonation. (1) The shape of the combustion chamber. (2) The relative position of the sparking plugs in case of petrol engines. (3) The chemical nature of the fuel. (4) The initial temp & pressure of fuel (5) The rate of combustion of that portion of fuel which is the first to ignite. This portion of fuel in heating up , compresses the remaining unburnt fuel, thus producing the condition for auto ignition to occur.