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131.

The knocking tendency in a compression ignition engine for a given fuel will

A.	Enhance by reducing compression ratio	B.	Enhance by increasing compression ratio
C.	Depend on other factors	D.	Increase to certain limits and then no change
E.	None of the above

132.

Total sulphur content in a diesel fuel oil must not exceed

A.	1%	B.	0.50%
C.	0.10%	D.	0.05%
E.	0.01%

133.

Which fuel will have least air consumption during combustion

A.	Gasoline	B.	Benzol
C.	Spirit	D.	Diesel fuel oil
E.	Lubricating oil

134.

A mixture containing 60% cetane and 40% Iso-octane will have

A.	Cetane number 60	B.	Cetane number 40
C.	Octane number 60	D.	Octane number 40
E.	None of the above

135.

Anti-knock for compression ignition engines is

A.	Amyl nitrate	B.	Tetra ethyl lead
C.	Trimethyl pentane	D.	Hexadecane
E.	Aromatics

136.

For same output and same compression ratio four stroke SI engines as compared to two stroke engines have

A.	Higher fuel consumption	B.	Lower thermal efficiency
C.	Higher thermal efficiency	D.	Higher exhaust temperatures
E.	None of the above

137.

In a four stroke engine if a valve opens 25? before B.D.C. and closes 10? after T.D.C. the valve should be

A.	Inlet valve	B.	Exhaust valve
C.	Puppet valve	D.	Spring valve
E.	Cam valve

138.

In spark ignition engines the knocking tendency decreases

A.	As compression ratio is reduced	B.	By controlling air/fuel mixture
C.	By controlling ignition timing	D.	By controlling exhaust temperatures
E.	None of the above

139.

Thermal efficiency of a standard Otto cycle for a compression ratio 5.5, will be

A.	20%	B.	35.40%
C.	47.50%	D.	50%
E.	100%

140.

If the pressures at the beginning and end of compression in an Otto cycle engine are 1 kg/cm2 and 8 kg/cm2 respectively the air standard efficiency will be

A.	57%	B.	50%
C.	45%	D.	40%
E.	50%