I.C Engines Objective Questions with Answers – Set 13

Are you guys looking for Mechanical Engineering MCQ Questions with Answers PDF Free Download as per Mechanical Engineering new exam pattern? You came to the right page. This may assist you to understand and check your knowledge about the Subjects. Students also can take a free test of the Multiple Choice Questions of Mechanical Engineering. Each question has four options followed by the right answer. These Mechanical Engineering MCQ Questions are selected supported by the newest exam pattern.

Q1. The pressure and temperature at the end of compression stroke in a petrol engine are of the order of

(A) 4-6 kg/cm² and 200-250°C
(B) 6-12 kg/cm² and 250-350°C
(C) 12-20 kg/cm² and 350-450°C
(D) 20-30 kg/cm² and 450-500°C

Answer: (B) 6-12 kg/cm² and 250-350°C

Q2. The knocking tendency in compression ignition engines for a given fuel will be

(A) Enhanced by decreasing compression ratio
(B) Enhanced by increasing compression ratio
(C) Dependent on other factors
(D) None of the above

Answer: (A) Enhanced by decreasing compression ratio

Q3. Engine pistons are usually made of aluminium alloy because it

(A) Is lighter
(B) Wear is less
(C) Absorbs shocks
(D) Is stronger

Answer: (A) Is lighter

Q4. In a petrol engine, the mixture has the lowest pressure at the

(A) Beginning of suction stroke
(B) End of suction stroke
(C) End of compression stroke
(D) None of these

Answer: (B) End of suction stroke

Q5. Gaseous fuel guarantees are based on

(A) Calorific value of oil
(B) Low heat value of oil
(C) High heat value of oil
(D) Mean heat value of oil

Answer: (B) Low heat value of oil

Q6. In order to eliminate knocking in compression ignition engines, there should be

(A) Short delay period
(B) Late auto-ignition
(C) Low compression ratio
(D) High self ignition temperature of fuel

Answer: (A) Short delay period

Q7. The output of a diesel engine can be increased without increasing the engine revolution or size in following way

(A) Feeding more fuel
(B) Heating incoming air
(C) Scavenging
(D) Supercharging

Answer: (D) Supercharging

Q8. The pressure at the end of compression, in diesel engines, is approximately

(A) 10 bar
(B) 20 bar
(C) 25 bar
(D) 35 bar

Answer: (D) 35 bar

Q9. In diesel engine, the compression ratio in comparison to expansion ratio is

(A) Same
(B) Less
(C) More
(D) Variable

Answer: (C) More

Q10. In a four stroke cycle diesel engine, the inlet valve

(A) Opens at 20° before top dead center and closes at 40° after bottom dead center
(B) Opens at 20° after top dead center and closes at 20° before bottom dead center
(C) Opens at top dead center and closes at bottom dead center
(D) May open and close anywhere

Answer: (A) Opens at 20° before top dead center and closes at 40° after bottom dead center

Q11. In order to mix air and petrol in the required proportion and to supply it to the engine during suction stroke, then _ is employed.

(A) Fuel pump
(B) Injector
(C) Carburettor
(D) None of these

Answer: (C) Carburettor

Q12. A higher compression ratio causes

(A) Pre-ignition
(B) Increase in detonation
(C) Acceleration in the rate of combustion
(D) Any one of these

Answer: (D) Any one of these

Q13. A petrol engine has compression ratio from

(A) 6 to 10
(B) 10 to 15
(C) 15 to 25
(D) 25 to 40

Answer: (A) 6 to 10

We hope the given Mechanical Engineering MCQ Questions with Answers will definitely yield fruitful results. Hope you got enough ideas on the MCQs on Mechanical Engineering. If you have any queries related to Mechanical Engineering MCQs Multiple Choice Questions with Answers, drop your questions below and will get back to you in no time.