MDE 1 End of Unit Quiz

MDE 1 End Of Unit Quiz

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1. Purpose of the Compression Stroke

Question: What is the primary purpose of the compression stroke in a four-stroke marine diesel engine?

D) To draw fresh air into the cylinder

A) To expel exhaust gases from the cylinder

B) To ignite the air-fuel mixture

C) To compress the air in the cylinder

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7. Role of the Compression Stroke in Power Output

Question: How does the compression stroke affect the power output of a marine diesel engine?

C) It prepares the air for combustion, indirectly contributing to power output

D) It has no effect on power output

A) It directly increases the power output by compressing the fuel

B) It reduces power output by increasing engine resistance

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4. Air-Fuel Mixture in Intake Stroke

Question: What is drawn into the cylinder during the intake stroke in a marine diesel engine?

A) A mixture of air and fuel

B) Pure fuel

D) Exhaust gases

C) Pure air

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5. Timing of Fuel Injection

Question: When is fuel typically injected into the cylinder of a marine diesel engine?

D) During the exhaust stroke

B) At the beginning of the compression stroke

C) At the end of the compression stroke

A) During the intake stroke

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10. Supercharging

Question: Which of the following is a benefit of supercharging in a marine diesel engine?

B) Increased engine efficiency and power output

D) Improved fuel quality

A) Reduced engine weight

C) Lower exhaust emissions

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8. Exhaust System in Diesel Engines

Question: What is the role of the exhaust system connected to the cylinder during the exhaust stroke?

D) It injects fuel into the cylinder

C) It channels the exhaust gases out of the engine

A) It cools down the intake air

B) It filters the air entering the cylinder

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8. Common Issues During Compression Stroke

Question: What could be a possible cause of reduced compression in a marine diesel engine?

C) Worn piston rings or cylinder liner

A) Faulty fuel injectors

B) Clogged air filters

D) Low coolant level

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8. Common Issues During Compression Stroke

Question: What could be a possible cause of reduced compression in a marine diesel engine?

C) Worn piston rings or cylinder liner

B) Clogged air filters

D) Low coolant level

A) Faulty fuel injectors

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2. Valve Operation During Compression Stroke

Question: During the compression stroke of a four-stroke marine diesel engine, which valves are closed?

C) Exhaust valve only

B) Intake valve only

A) Both intake and exhaust valves

D) Both intake and exhaust valves are open

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5. Timing of the Intake Stroke

Question: When does the intake stroke begin in the four-stroke cycle of a marine diesel engine?

C) Immediately after the exhaust stroke

A) Immediately after the compression stroke

D) Immediately after the intake valve closes

B) Immediately after the power stroke

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3. Piston Movement in Compression Stroke

Question: In which direction does the piston move during the compression stroke of a four-stroke marine diesel engine?

A) Downward away from the cylinder head

D) Moves sideways within the cylinder

B) Upward toward the cylinder head

C) Remains stationary

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Factors Influencing Penetration

Question: Which of the following factors primarily influence the penetration of fuel in the combustion chamber of a marine diesel engine?

D) Compression ratio and turbocharger boost

B) Engine speed and intake air temperature

C) Fuel density and exhaust pressure

A) Fuel temperature and injector nozzle design

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