In four stroke engine which of the following is also known as power stroke a. Suction stroke b. Compression stroke c. Expansion stroke d. Exhaust stroke (Ans:c) Measurements of fuel and air consumption, brake power and incylinder pressure. Tutorials on engine performance parameters. Heat balance sheet. Engine performance curves. 1. The increase in intake air temperature into IC engine,___________its efficiency A. increase B. decrease C. does not alter D. unpredictable on

In four stroke engine which of the following is also known as power stroke a. Suction stroke b. Compression stroke c. Expansion stroke d. Exhaust stroke (Ans:c) Measurements of fuel and air consumption, brake power and incylinder pressure. Tutorials on engine performance parameters. Heat balance sheet. Engine performance curves. 1. The increase in intake air temperature into IC engine,___________its efficiency A. increase B. decrease C. does not alter D. unpredictable on  
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In a two stage reciprocating air compressor, the suction and delivery pressure are 1 and 4 bar respectively. For maximum efficiency the intercooler pressure is A. 1.5 bar B. 2 bar C. 2.5 bar D. 3 bar

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If one cylinder of a diesel engine receives more fuel than others , then for that cylinder the A. exhaust will be smoky B. scavenging occurs C. exhaust temperature will be high D. engine starts overheating

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Which one of the following statement is not correct for the volumetric efficiency of a reciprocating air compressor? A. It decreases with increase in ambient temperature B. It increases with decrease in pressure ratio C. It increases with decrease in clearance ratio D. It decreases with increases in delivery pressure

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The thermal efficiency of a diesel cycle having fixed compression ratio with increase in cut-off ratio will a. increase b. decrease c. independent d. increase or decrease depending upon other factors

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If the compression ratio of an engine working on Otto cycle is increased from 5 to 7 the percentage increase in efficiency will be a. 2% b. 4% c. 8% d. 14%

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The reason for supercharging in any engine is to be A. increase efficiency B. increase power C. effect fuel economy D. reduce weight and bulk for a given output

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In vapour compression cycle using NH3 as refrigerant, initial charge is filled at (a) suction of compressor (b) delivery of compressor (c) high pressure side close to receiver (d) low pressure side near receiver

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For minimum work input in a two stage compression process the intermediated pressure is the A. Arithmetic process of suction and discharge pressure B. Logarithmic mean of suction and discharge pressure C. Geometric mean of suction and discharge pressure D. Hyperbolic mean of suction and discharge

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In compression ignition (CI) engine, the compression ratio is a. Cylinder volume / Clearance volume b. Swept Volume / Cylinder Volume c. Clearance volume / Cylinder volume d. Cylinder volume / Swept volume (Ans:a)

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Last Answer : In two stroke engine there is one power stroke in _____ of crankshaft rotation. a. 90° b. 180° c. 270° d. 360° (Ans:d)

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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Rate of burning in the compression ignition engine can be controlled by a. rate of injection of fuel b. rate of air taken into carburetor c. both a. and b. d. none of the above

Description : Rate of burning in the compression ignition engine can be controlled by a. rate of injection of fuel b. rate of air taken into carburetor c. both a. and b. d. none of the above

Last Answer : ANSWER a. rate of injection of fuel

The knocking tendency in CI engines increases with (a) Increase of coolant water temperature (b) Increase of temperature of inlet air (c) Decrease of compression ratio (d) Increase of compression ratio

Description : The knocking tendency in CI engines increases with (a) Increase of coolant water temperature (b) Increase of temperature of inlet air (c) Decrease of compression ratio (d) Increase of compression ratio

Last Answer : Ans :c

The tendency of knocking in CI engine reduces by (a) High self ignition temperature of fuel (b) Decrease in jacket water temperature (c) Injection of fuel just before TDC (d) Decrease in injection pressure

Description : The tendency of knocking in CI engine reduces by (a) High self ignition temperature of fuel (b) Decrease in jacket water temperature (c) Injection of fuel just before TDC (d) Decrease in injection pressure

Last Answer : Ans :c

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Description : Disadvantage of hydrogen as a fuel in IC engine is a) storage is safe b) low NOx c) detonating tendency d) easy handling

Last Answer : Answer: c Explanation: None.

Morse test is conducted on the engine to calculate the mechanical efficiency of A. single cylinder CI engine B. single cylinder SI engine C. only on two stroke engines D. multi cylinder engine

Description : Morse test is conducted on the engine to calculate the mechanical efficiency of A. single cylinder CI engine B. single cylinder SI engine C. only on two stroke engines D. multi cylinder engine

Last Answer : ANSWER : D

A gas engine has a volume of 300 cc and clearance volume of 25 cc. Its volumetric efficiency is 0.8 and mech efficiency is 0.9. What is the volume of the mixture taken in per stroke? (a) 248 cc (b) 252 cc (c) 264 cc (d) 286 cc

Description : A gas engine has a volume of 300 cc and clearance volume of 25 cc. Its volumetric efficiency is 0.8 and mech efficiency is 0.9. What is the volume of the mixture taken in per stroke? (a) 248 cc (b) 252 cc (c) 264 cc (d) 286 cc

Last Answer : Ans : c