The compression ratio in a Spark Ignition (SI) engine is generally in between a. 7 to 10 b. 10 to 14 c. 14 to 18 d. 18 to 22 (Ans:a)

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Which of the following is not true for two stroke engine as compared to four stroke engine? a. Less cooling is required b. Greater lubrication is required c. More uniform torque on crankshaft d. Complete exhaust of products of combustion (Ans:a)

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Last Answer : ANSWER c. The compression ratio of a diesel engine is higher than that of an S.I engine

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Last Answer : ANSWER b. compression ignition engine

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Last Answer : Answer: d Explanation: None.

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Last Answer : Ans :c

Description : For spark ignition engine, the equivalence ratio of mixture entering the combustion chamber has values (A) for idling and for peak power conditions (B) for both idling and peak power conditions (C) for idling and for peak power conditions (D) for both idling and peak power conditions

Last Answer : ANSWER (B) for both idling and peak power conditions

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Last Answer : ANSWER : C

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Last Answer : ANSWER c. Both a and b.

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Last Answer : ANSWER a. fuel injector

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Last Answer : ANSWER c. Both a and b

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Description : Use of gasoline blend like tetraethyl lead in internal combustion engine a. increases the octane rating of the fuel b. allows engine to operate at higher compression ratio c. avoids auto-ignition of fuel d. all of the above

Last Answer : ANSWER d. all of the above

Description : The compression ratio cannot be increased beyond certain limit as it results in a. auto-ignition of fuel b. detonation c. engine knocking d. all the above

Last Answer : ANSWER d. all the above

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Last Answer : Ans :a

Description : For the same capacity engines, the compression ratio of diesel engine a. is lower than the compression ratio of SI engine b. is higher than the compression ratio of SI engine c. is same as the compression ratio of SI engine d. cannot say

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Last Answer : ANSWER : C

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Last Answer : ANSWER : A

Description : Combustion in compression ignition engine is a. homogeneous b. heterogeneous c. laminar d. turbulent

Last Answer : ANSWER b. heterogeneous

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Last Answer : Option D

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Last Answer : ANSWER : D

Description : The accumulation of carbon in a cylinder results in increase of a. clearance volume b. volumetric efficiency c. ignition time d. effective compression ratio

Last Answer : ANSWER d. effective compression ratio

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Last Answer : Option B

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