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Combustion MCQ

What is the law of conservation of mass?

The law that states that the total energy in a system remains constant

The idea that mass is not lost or gained during a chemical reaction

The law that states that the total mass of a system remains the same over time

The law that states that the total mass of a system remains constant

Answer

Correct Answer: The idea that mass is not lost or gained during a chemical reaction

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What does the presence of wind turbines interfere with?

Solar energy

Radioactivity

Mammals

Bird migration

Answer

Correct Answer: Bird migration

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What type of power is noisy?

Solar power

Wind power

Nuclear power

Gasoline powered vehicles

Answer

Correct Answer: Wind power

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The advantage of solar energy is clean and what?

Inexhaustible

Safe

Economical

More reliable

Answer

Correct Answer: Inexhaustible

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Where does nuclear energy produce electricity?

Wind turbines

Power station factories

Hydro dams

Solar panels

Answer

Correct Answer: Power station factories

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What kind of technology does the term "The Green Revolution" refer to?

Electronics

Computing

Agricultural

Medical

Answer

Correct Answer: Agricultural

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What are two examples of new agricultural technology?

Irrigation systems

High-yield seeds and fertilizers

Greenhouse gas technology

Robotics in agriculture

Answer

Correct Answer: High-yield seeds and fertilizers

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What does the term "Green Revolution" refer to?

Rapid diffusion of new agricultural technology

The increase in agricultural production in China during the 1960s

The advent of chemical fertilizers that increase crop yields

The increase in agricultural production between the 1940s and 1970s

Answer

Correct Answer: Rapid diffusion of new agricultural technology

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What are fossil fuels?

Paper, hydroelectricity

Wood, solar, wind

Diamonds, gold, silver

Coal, oil, natural gas

Answer

Correct Answer: Coal, oil, natural gas

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What kind of injury is hypothermia?

Brain damage

Inadequate heat production

Abnormally low body temperature

Broken bone

Answer

Correct Answer: Abnormally low body temperature

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Who is the God of Fire in the Mahuika religion?

Ranginui

Te Kooti

Polynesian gods

Mahuika Māori

Answer

Correct Answer: Mahuika Māori

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What are some of the properties of petrol?

Burns clean

Easily ignites

Low boiling point and strong smell

Turns to liquid at low temperatures

Produces heat when burned

Answer

Correct Answer: Low boiling point and strong smell

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A combination of gases compressed into a liquid is called what?

LPG

L.P.G

Hydrocarbons

GAS

Answer

Correct Answer: L.P.G

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What are the three factors that cause the release of energy in a fire?

Oxygen, heat and light

Oxygen, heat and a spark

Heat, oxygen and a fuel

Oxygen, heat and a fuel

Answer

Correct Answer: Oxygen, heat and a fuel

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Oxygen is used to help the body's cells stay in good health, what else is needed to maintain the cells?

Creatine

Red blood cells

Potassium

Iron

Answer

Correct Answer: Red blood cells

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Oxygen is necessary to carry around what?

Water

Blood

Food

Body

Answer

Correct Answer: Body

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What is the SI unit of energy?

Joules/BTUs

Joules

BTUs

Calorie

Answer

Correct Answer: Joules

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What is respiration?

The involuntary action of breathing

The process by which cells generate energy

The process by which cells break down simple food molecules

The process by which the body gets energy from food

Answer

Correct Answer: The process by which cells break down simple food molecules

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What splint was reignited when tested for the presence of oxygen?

Glowing

Blue

Green

Red

Answer

Correct Answer: Glowing

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When the splint is reignited, what does it test for?

Presence of oxygen

Presence of heat

Presence of water vapor

Presence of carbon dioxide

Answer

Correct Answer: Presence of oxygen

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What is the chemical formula of methane?

CO2

CH4

N2O

Answer

Correct Answer: CH4

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What is a type of reaction that ABSORBS energy?

Exothermic reaction

Catalytic reaction

Oxidative reaction

Endothermic reaction

Answer

Correct Answer: Endothermic reaction

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Exothermic reactions release energy in the form of what?

Heat

Gas

Pressure

Light

Answer

Correct Answer: Heat

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What does complete combustion produce?

Nitrogen and water

Carbon dioxide, nitrogen, and oxygen

Carbon dioxide and heat

Carbon dioxide and water

Answer

Correct Answer: Carbon dioxide and water

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What type of fuel is burned to produce Carbon Dioxide?

Incandescent

Renewable

Fossil

Nuclear

Answer

Correct Answer: Fossil

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What does burning fossil fuels produce?

Pollution

Heat

Water vapor

Carbon Dioxide

Answer

Correct Answer: Carbon Dioxide

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What can be reversed with a reaction?

Chemical reaction

Mental change

Chemical change

Physical change

Answer

Correct Answer: Physical change

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What is the definition of an irreversible reaction?

Kinetic energy

Chemical change

Nuclear reaction

Energy transfer

Answer

Correct Answer: Chemical change

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What is an example of an ending material in a chemical reaction?

Reactants

Intermediates

Products

Heat

Answer

Correct Answer: Products

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What is a starting material in a chemical reaction?

Reactants

Catalyst poisons

Catalyst

Solvent

Answer

Correct Answer: Reactants

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What is the name of the substance that is formed when something is burned and there isn't enough oxygen?

Dust

Ash

Smoke

Soot

Answer

Correct Answer: Soot

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What is the main component of crude oil?

Sulfur

Methane

Pollen

Hydrocarbon

Answer

Correct Answer: Hydrocarbon

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What is a product of incomplete combustion?

Carbon monoxide

Oxides of nitrogen

Nitrogen dioxide

Carbon dioxide

Answer

Correct Answer: Carbon monoxide

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What can not be replaced and will run out?

Nonrenewable fuels

Coal

Nuclear power

Fossil fuels

Answer

Correct Answer: Nonrenewable fuels

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What can be replaced and will not run out?

Renewable fuels

Coal

Nuclear power

Fossil fuels

Answer

Correct Answer: Renewable fuels

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What means a substance that burns and releases energy?

Fuel for an engine

Fuel

Solid

Lighter

Answer

Correct Answer: Fuel

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What does a fuel release?

Energy

Waste

Nitrogen

Oxygen

Answer

Correct Answer: Energy

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What does global warming cause changes to?

The environment

The climate

The weather

Answer

Correct Answer: The weather

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What could the changes in the weather be due to?

A solar eclipse

A meteor shower

Global warming

The moon landing

Answer

Correct Answer: Global warming

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What could an environmental pollutant do to organisms in the ecosystem?

Alter the environment

Kill

Damage

Harm

Cause mutations

Answer

Correct Answer: Harm

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What kind of substance can harm the environment?

Element

Liquid

Solid

Pollutant

Answer

Correct Answer: Pollutant

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What type of reaction can occur in incomplete combustion?

No reaction

Partial

Complete

Answer

Correct Answer: Partial

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What term refers to a substance reacting only partially with oxygen?

Incomplete combustion

Oxidizer

Reaction

Oxidation

Answer

Correct Answer: Incomplete combustion

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When a fuel reacts fully with oxygen, to produce heat, carbon dioxide, and water is called?

Light

Fire

Complete combustion

Water

Answer

Correct Answer: Complete combustion

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What is the precipitation that is more acidic than usual due to air pollution?

Sulfuric acid rain

Nitric acid rain

Snow

Acid rain

Answer

Correct Answer: Acid rain

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What causes acidic rain?

Volcanoes

Air pollution

Acid rain

Acid rain from factories

Answer

Correct Answer: Air pollution

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What is an example of a type of extinguisher?

Nitrogen dioxide, powder, water or foam

Carbon dioxide, powder, water or foam

A fire extinguisher with a foam nozzle

A fire extinguisher that uses pressurized CO2

Answer

Correct Answer: Carbon dioxide, powder, water or foam

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What does something that is used to put out a fire do?

Extinguisher

Flashlight

Fire extinguisher

Fire blanket

Answer

Correct Answer: Extinguisher

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What are some examples of non-metals?

Non-metals are elements that cannot be divided by chemical reactions

Non-metals don't form compounds with other elements

Any element that is not shiny doesn't conduct heat and electricity well

None of these

Answer

Correct Answer: Any element that is not shiny doesn't conduct heat and electricity well

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What kind of element isn't shiny?

Non-metal

Non-metallic

Plastic

Glass

Answer

Correct Answer: Non-metal

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What is an example of a characteristic that defines metal?

Durable

Metallic

Unbreakable

Shiny

Answer

Correct Answer: Shiny

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What is a property of metal?

Metallic

Strong

Malleable

Durable

Answer

Correct Answer: Malleable

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What does a metal often have?

A high electrical resistivity

A high melting point

A crystalline structure

A low melting point

Answer

Correct Answer: A high melting point

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What is the A/F ratio compared to?

Avogadro's number

Molecular weight

Temperature

Stoichiometry

Answer

Correct Answer: Stoichiometry

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What is the value at which the rate of A/F approaches stoichiometry?

∞

Answer

Correct Answer: Λ

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What is A/F ratio defined as?

Volumetric Air/Fuel ratio

Relative Air/Fuel ratio

Fuelling efficiency

Absolute Air/Fuel ratio

Answer

Correct Answer: Relative Air/Fuel ratio

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What is the A/F ratio of stoichiometry?

0.8

0.6

1.0

3.0

2.0

Answer

Correct Answer: 1.0

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How many times between TDC and BDC is the cylinder volume?

Cylinder head volume

Piston displacement

Exhaust gas recirculation volume

In-cylinder volume

Swept volume

Answer

Correct Answer: Swept volume

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What is the swept volume between TDC and BDC?

Volume of the combustion chamber

Volume of the cylinder

Volume of the air/fuel mixture

Volume of the piston

Answer

Correct Answer: Volume of the cylinder

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What is the value of Clearance Volume in cubic centimetres at the top of its range?

Volume of the combustion chamber

Volume of the intake manifold

Volume of the turbocharger

Volume of the exhaust manifold

Answer

Correct Answer: Volume of the combustion chamber

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What is the name of the volume of the combustion chamber when the piston is at TDC?

Exhaust Port Volume

Intake Port Volume

Clearance Volume

Exhaust Volume

Intake Volume

Answer

Correct Answer: Clearance Volume

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What is the unit of measure for injection duration?

Milliseconds

Minutes

Seconds

Microseconds

Hours

Answer

Correct Answer: Microseconds

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What is the generally expressed in microseconds?

Battery voltage

Injection pressure

Injection duration

Injection time

Motor speed

Answer

Correct Answer: Injection duration

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What does "Top Dead Center" mean?

When the piston is in the middle of the cylinder

When the piston is at the bottom of the cylinder

When the piston is at the top of the cylinder

When the gun is pointed in the ground

When the firing pin is resting on an empty chamber

Answer

Correct Answer: When the piston is at the top of the cylinder

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What is the term for the position of the piston just before the top of the cylinder?

Topmost

Bottom Dead Center

Mid-stroke

Top Dead Center

Answer

Correct Answer: Top Dead Center

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What is the name of the point on the piston's travel path at which the cylinder is at its highest point?

Midpoint of the Piston's Travel Path

Top Dead Center

Second Top Dead Center

Bottom Dead Center

Answer

Correct Answer: Top Dead Center

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What is the main feature of the engine that affects its temperature?

Fuel

Air

Cylinder

Answer

Correct Answer: Cylinder

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What is the term used to describe the heat given off by an engine that has been running?

Operating temperature

Intake air temperature

Engine temperature

Cylinder temperature

Exhaust gas temperature

Answer

Correct Answer: Cylinder temperature

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What type of timing is expressed in crank angle degrees?

Carburetor

EFI

Fuel Injection

Carburation

Injection

Answer

Correct Answer: Injection

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What is the measurement of injection timing expressed in?

Engine speed rpm

Injector pulsewidth

Revs per minute

Crank angle degrees

Answer

Correct Answer: Crank angle degrees

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What type of engine is an example of an Spark Ignition engine?

Gasoline

Dual ignition

Spark ignited

Diesel

Compression ignition

Answer

Correct Answer: Spark ignited

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What is an example of a spark ignited engine?

Gasoline Engine

Diesel Engine

Carburetor

Spark Ignition

Injection Pump

Answer

Correct Answer: Spark Ignition

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Spark Advance is expressed in what unit?

Crank angle degrees

Watts

Volt

Amp

Horsepower

Answer

Correct Answer: Crank angle degrees

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What is the term for spark timing expressed in crank angle degrees?

Spark advance

Ignition timing

Spark retard

Timing adjustment

Answer

Correct Answer: Spark advance

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What would be the result if the crank angle was 10% MFB?

No change

Less Torque

More Torque

The timing belt would slip

Crank Angle for 10% MFB

Answer

Correct Answer: Crank Angle for 10% MFB

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What percentage of a person's weight can be applied to their back?

20%

10%

30%

Answer

Correct Answer: 10%

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What does 'mass fraction burned' describe?

The weight of a substance

The mass of the substance

The weight of material burned

The process of chemical energy release

The average mass of material burned

Answer

Correct Answer: The process of chemical energy release

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What is the scale of the Mass Fraction Burned?

1 to 10

10 to 100

0 to 1

1 to 100

0.1 to 10

Answer

Correct Answer: 0 to 1

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What determines the lower heating value?

The amount of heat required to vaporize the water

Subtracting the heat of vaporization of the water vapor

The weight of the water

The specific heat of the water

Answer

Correct Answer: Subtracting the heat of vaporization of the water vapor

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How determined by subtracting the heat of vaporization of the water vapor?

Lower Heating Value

Higher Heating Value

Temperature of boiling water

Not Determinant

Answer

Correct Answer: Lower Heating Value

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What type of ignition is undesired?

Ignition interference

Pilot light

Auto-ignition

Spark

A spark from the plug gap

Answer

Correct Answer: Auto-ignition

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What do you call an undesired auto-ignition appearing in an unburned area of the combustion chamber?

Knock

Blowtorch

Fireball

Blow

Answer

Correct Answer: Knock

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What does the term "Knock" mean?

A summons to enter

A door knock

Undesired auto-ignition

Calling out someone's name

Answer

Correct Answer: Undesired auto-ignition

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What does the acronym IND indicate?

Indian National Drug Control Program

Indian National Diet

Indicated Specific Fuel Consumption

Insurance Department

Indicate New Directions

Answer

Correct Answer: Indicated Specific Fuel Consumption

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What is indicated specific fuel consumption based on?

The operating temperature

The gear ratio

The engine speed

The engine in-cylinder pressures

Answer

Correct Answer: The engine in-cylinder pressures

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What does indicated specific fuel consumption represent?

Specific fuel consumption for a given driving situation

Specific fuel consumption based on the vehicle's speed

Specific fuel consumption based on the vehicle's weight

Specific fuel consumption for a given power level

Specific fuel consumption based on the engine in-cylinder pressures

Answer

Correct Answer: Specific fuel consumption based on the engine in-cylinder pressures

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How many cycles do two-stroke engines have versus four-stroke engines?

120°

360°

180°

60°

Answer

Correct Answer: 360°

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What is calculated from in cylinder pressure?

Stroke pressure

Peak cylinder pressure

Static pressure

Dynamic pressure

Mean effective pressure

Answer

Correct Answer: Mean effective pressure

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How long is the engine cycle in a 4 stroke engine?

720°

2,160°

1,440°

1080°

1440°

Answer

Correct Answer: 720°

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In a homogeneous charge, what type of ignition is used?

Combustion Ignition

Charge Compression Ignition

Spark Ignition

Thermionic Ignition

Answer

Correct Answer: Charge Compression Ignition

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What type of ignition uses a spark plug to create the spark?

Proprietary Diesel

Spark-Ignition

Compression Ignition

Homogeneous Charge Compression Ignition

Direct Injection

Answer

Correct Answer: Homogeneous Charge Compression Ignition

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What is the name of the mean effective pressure lost due to engine friction?

Pressure Drops

Pressure Losses

Turbine Mean Effective Pressure

Friction Mean Effective Pressure

Fan Mean Effective Pressure

Answer

Correct Answer: Friction Mean Effective Pressure

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What is the ratio in a reciprocating engine?

Air/Fuel

Fuel/Air and Steam

Fuel/Exhaust

Fuel/Air

Answer

Correct Answer: Fuel/Air

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How does the use of exhaust gas recirculation help with NOx emission?

Emitting

Reducing

Controlling

Answer

Correct Answer: Controlling

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What does the term "EGR" stand for?

Exhaust Gas Recirculation Valve

Exhaust Gas Removal

Exhaust Gas Recirculation

Engineered Gas Reform

Engine Block Hugger

Answer

Correct Answer: Exhaust Gas Recirculation

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A compression ratio is a fundamental specification for what?

Airbags

The amount of air an engine can use

Many common combustion engines

Engine valves

The pressure inside a gas tank

Answer

Correct Answer: Many common combustion engines

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What is the value that represents the ratio of the volume of engine combustion chamber from its largest capacity to its smallest capacity?

Octane Rating

Compression Ratio

Displacement

Horsepower

Volume

Answer

Correct Answer: Compression Ratio

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What percentage of heat is released by the crank?

90%

80%

70%

95%

Answer

Correct Answer: 70%

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What is the term used to describe the portion of the crank that releases 50% of the heat?

Camshaft position

Crank angle position

Valve timing

Timing belt

Answer

Correct Answer: Crank angle position

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Brake Specific Fuel Consumption is used for what comparison?

Comparing the efficiency of internal combustion engines with electric motors

Comparing the efficiency of internal combustion engines with hybrid systems

Comparing the efficiency of internal combustion engines with a shaft output

Comparing the efficiency of gasoline engines with a diesel engine

Comparing the efficiency of diesel engines with a gasoline engine

Answer

Correct Answer: Comparing the efficiency of internal combustion engines with a shaft output

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What is a measurement used to compare the efficiency of internal combustion engine?

Horsepower

Brake Specific Fuel Consumption

Fuel Economy

Torque

Answer

Correct Answer: Brake Specific Fuel Consumption

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Brake mean effective pressure is similar to what during power stroke?

The real mean torque

The radially averaged torque

The effective pressure at the beginning of power stroke

The nominal torque

Answer

Correct Answer: The real mean torque

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What does bottom dead center mean?

When the engine reaches its operating temperature

When the bullet exits the barrel

At the point where the piston makes contact with the cylinder

When the firing pin hits the primer

When the piston is at the bottom of the cylinder

Answer

Correct Answer: When the piston is at the bottom of the cylinder

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What is the term for when the piston is at its lowest position in the cylinder?

Bottom Dead Center

No Gas

Top Dead Center

Intake valves are open

Answer

Correct Answer: Bottom Dead Center

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