PRIME'S ELEMENTS IN PIPE : CHAPTER 2 FUELS & COMBUSTION

PAST BOARD QUESTION

Which is not a viscosity rating?

A. Redwood

B. SSU

C. Centipoise

D. Entropy Degrees API

D. Entropy Degrees API

PAST BOARD QUESTION

Percent excess air is the difference between the air actually supplied and the theoretically required divided by.

A. the theoretically air supplied

B. the actually air supplied

C. the deficiency of air supplied

D. the sufficient air supplied

A. the theoretically air supplied

PAST BOARD QUESTION

What is the apparatus used in the analysis of combustible gases?

A. Calorimeter differential

B. Calorimeter gas

C. Calorimetry

D. Calorimeter

D. Calorimeter

PAST BOARD QUESTION

Percent excess air is the difference between the air actually supplied and the theoretical air divided by

A. the sufficient air supplied

B. the deficiency air supplied

C. the actually air supplied

D. the theoretically air supplied

D. the theoretically air supplied

PAST BOARD QUESTION

The viscosity of most commercially available petroleum lubricating oil changes rapidly above

A. 120 ℉

B. 180 ℉

C. 150 ℉

D. 130 ℉

B. 180 ℉

PAST BOARD QUESTION

When 1 mol carbon combines with 1 mol oxygen

A. 2 mols carbon dioxide

B. 1 mol carbon dioxide

C. 1 mol carbon and 1 mol carbon dioxide

D. 1 mol carbon dioxide

B. 1 mol carbon dioxide

PAST BOARD QUESTION

What are the immediate undesirable products from the petroleum based lubricating oil when subjected to high pressure and temperature?

A. Gums, resins and acids

B. Sulfur

C. Soots and ashes

D. Carbon residue

A. Gums, resins and acids

What kind of boding do common gases that exist in free state as diatomic molecules experiences?

A. ionic bonds

B. covalent bonds

C. metallic bonds

D. nuclear bonds

B. covalent bonds

An Orsat's apparatus is used for

A. volumetric analysis of the flue gas

B. gravimetric analysis of the flue gas

C. smoke density analysis of the flue gas

D. all of the above

A. volumetric analysis of the flue gas

A theorem that states that the total property of a mixture of ideal gases is the sum of the properties that the individual gases would have if each occupied the total mixture volume alone as the same temperature.

A. Gibbs theorem

B. Dalton's theorem

C. Boltzmann's theorem

D. Maxwell's theorem

A. Gibbs theorem

A small enough particles suspended in a fluid exhibit small random movements due to the state collision of fluid molecules on the particle's sum. This motion is called____________.

A. Boltzmann motion

B. Rectilinear motion

C. Kinetic gas motion

D. Brownian motion

D. Brownian motion

When two or more light atoms have sufficient emf (available only at high temperatures and velocities) fuse together to form a heavier nucleus the process called____________.

A. fusion

B. fission

C. the photo electric effect

D. the Compton effect

A. fusion

What is the residue left after combustion of a fuel?

A. charcoal

B. ash

C. scraper

D. all of the choices

B. ash

What is formed during incomplete combustion of carbon in fuels?

A. carbon dioxide

B. carbon monoxide

C. nitrogen oxide

D. oxygenated fuel

B. carbon monoxide

A gas produced by the combustion of fuel oil and cannot be found in the flue gases is:

A. oxygen

B. nitrogen

C. hydrogen

D. carbon dioxide

C. hydrogen

Which of the following chemical reactions in which heat is absorbed?

A. heat reaction

B. endothermic reaction

C. exothermic reaction

D. combustion reaction

B. endothermic reaction

A chemical reaction in which heat is given off.

A. heat reaction

B. endothermic reaction

C. exothermic reaction

D. combustion reaction

C. exothermic reaction

Colorless, odourless mixture of nitrogen and oxygen with traces of other gases water vapour and said impurities.

A. air

B. helium

C. water gas

D. nitrite

A. air

The transfer of air characteristics by horizontal motion is called____________.

A. convection

B. air transfer

C. advection

D. adhesion

C. advection

Properties of non - reacting gas mixtures are given by

A. geometric weighting

B. volumetric weighting

C. volumetric weighting for molecular weight and density, and geometric weighting for all other properties except entropy

D. arithmetic average

C. volumetric weighting for molecular weight and density, and geometric weighting for all other properties except entropy

The process of separating two or more liquids by means of the difference in their boiling point.

A. Engler distillation

B. Fractional distillation

C. Gas scrubbing

D. Fractional crystallization

B. Fractional distillation

The gaseous products of combustion of a boiler which contains carbon dioxide, carbon monoxide, oxygen, nitrogen and water vapour is called____________.

A. flue gas

B. producer gas

C. product gas

D. universal gas

A. flue gas

A substance whose burning with oxygen yields heat energy such as coal, petroleum and natural gas.

A. air

B. fluid

C. fuel

D. gas

C. fuel

Stoichiometric ratio is

A. chemically correct air - fuel ratio by volume

B. chemically correct air - fuel ratio by weight

C. theoretically mixture of air for complete combustion

D. actual ratio of air to fuel for maximum efficiency

B. chemically correct air - fuel ratio by weight

A type of radiation consisting of singly charged particles that generate to intermediate distances.

A. nuclear radiation

B. alpha radiation

C. beta radiation

D. gamma radiation

C. beta radiation

The increase in velocity past the throat is due to rapid decrease in the:

A. fluid density

B. fluid specific volume

C. fluid temperature

D. fluid pressure

A. fluid density

In an oxidation - reduction chemical reaction, all of the following occur except:

A. the exchange of electrons between elements

B. elements becoming more positive

C. elements becoming more negative

D. nuclear fusion

D. nuclear fusion

The residual oil left after the distillation of gasoline and kerosene from crude petroleum; yellow to brown and used as a diesel fuel and enriching water gas.

A. diesel oil

B. gasoline oil

C. LPG

D. gas oil

D. gas oil

A fuel gas obtained by the destructive distillation of soft coal is called__________.

A. gas scrub

B. coal gas

C. alco gas

D. water gas

B. coal gas

Removing of impurities from a gas by bubbling it through a liquid purifying agent is called__________.

A. gas scrubbing

B. gas purifying

C. gas liquefying

D. gas bubbling

A. gas scrubbing

During the fusion process, mass is lost and converted to energy according to:

A. the Heisenburg uncertainty principle

B. the Compton's law

C. Einstein's law

D. the second law of thermodynamics

C. Einstein's law

A finely divided carbon deposit by the smoke or flame is called__________.

A. fly ash

B. soot

C. residue

D. all of the choices

B. soot

Rare gases such as helium, argon, krypton, xenon and radon that are non - reactive are called_____________.

A. non - reactants

B. stop gases

C. insert gases

D. residual gases

C. insert gases

Kinematics and dynamic viscosity vary from each of only by a factor equal to the :

A. fluid density

B. temperature

C. pressure

D. specific gas constant

A. fluid density

The following properties are different for isomers of the same chemical compound:

A. density

B. melting point

C. number of atoms in a mole of each isomers

D. specific heat

C. number of atoms in a mole of each isomers

Atomic weights of the elements in the periodic table are not whole numbers because of:

A. the existence of isotopes

B. imprecise measurements during the development of the periodic table

C. round - off error in calculating atomic weights

D. the exchange of reference of the atomic mass unit from oxygen - 16 to carbon - 12 in 1961.

A. the existence of isotopes

The tendency of a pure compound to be composed of same elements combined in a definite proportion by mass.

A. Avogadro's law

B. Boyle's law

C. The law of definite proportions

D. Le Chatelier's principle

C. The law of definite proportions

How do you call the process of removing of impurities from a gas by bubbling it through a liquid purifying agent?

A. gas scrubbing

B. gas purifying

C. gas liquefying

D. gas bubbling

A. gas scrubbing

What is the effect of catalyst in a chemical reaction?

A. absorb the exothermic heat of reaction

B. provide the exothermic heat of reaction

C. lower the activation energy

D. provide the heat of sublimation

C. lower the activation energy

The relationship between the concentration of products and reactants in a reversible chemical reaction give by:

A. the ionization constant

B. the equilibrium constant

C. the solubility

D. Le Chatelier's principle

B. the equilibrium constant

What fuel gas obtained by the destructive distillation of soft coal?

A. gas scrub

B. coal gas

C. alcogas

D. water gas

B. coal gas

The process of splitting the nucleus into small fragments.

A. fusion

B. fission

C. the photo electric effect

D. the Compton effect

B. fission

The ash that is removed from the combustor after the fuel is burn is the:

A. fly ash

B. bottom ash

C. scraper ash

D. top ash

B. bottom ash

A mixture of hydrogen and carbon monoxide made by passing steam over hot coke.

A. water gas

B. water vapor

C. hydrocarbon

D. air

A. water gas

All of the following are true of non - stoichiometric reactions except.

A. there is an excess of one or more reactants

B. the percentage yield measures the efficiency of the reaction

C. non - stoichiometric reactions are rare in the combustion process

D. in combustion, air is often the excess reactant to assure complete combustion of fuel

C. non - stoichiometric reactions are rare in the combustion process

It is the ratio of the volume at the end of heat addition to the volume at the start of heat addition.

A. compression ratio

B. air - fuel ratio

C. volumetric ratio

D. cut - off ratio

D. cut - off ratio

Piston rings are made of:

A. alloy steel

B. carbon steel

C. copper

D. cast iron

D. cast iron

PAST BOARD QUESTION

Loss power is due to

A. poor compression

B. restricted exhaust

C. clogging of air cleaner

D. low injection pressure

D. low injection pressure

PAST BOARD QUESTION

How do you call a branch system of pipes to carry waste emissions away from the piston chambers of an internal combustion engine?

A. exhaust nozzle

B. exhaust deflection pipe

С. exhaust pipe

D. exhaust manifold

D. exhaust manifold

PAST BOARD QUESTION

The type of filter where the filtering elements is replaceable.

A. Paper edge filter

B. Metal edge filter

C. Pressure filter

D. Filter with element

B. Metal edge filter

PAST BOARD QUESTION

When four events takes place in one revolution of a crankshaft of an engine, the engine is called

A. rotary engine

B. steam engine

C. two stroke engine

D. four stroke engine

C. two stroke engine

PAST BOARD QUESTION

Which of the following does not belong to the group?

A. Air injection system

B. Mechanical injection system

C. Time injection system

D. Gas admission system

C. Time injection system

Specific heat capacity is an SI derived unit described as:

A. J/kg

B. W/m °K

C. J/m³

D. J/kg °K

D. J/kg °K

PAST ME BOARD QUESTION

A device whose primary function is to meter the flow refrigerant to the vapour.

A. sniffer valve

B. equalizer

C. thermostatic expansion valve

D. crossover valve

C. thermostatic expansion valve

PAST BOARD QUESTION

The internal combustion engines never work in

A. Rankine cycle

B. Diesel cycle

C. Dual combustion cycle

D. Otto cycle

A. Rankine cycle

The general chemical formula for all hydrocarbons 𝐶ₙ 𝐻ₘ. In different combinations of interest, as steam combustion engine fuel, n varies from:

A. 1 to 26

B. 2 to 54

C. 2 to 26

D. 1 to 54

A. 1 to 26

The general chemical formula for all hydrocarbons 𝐶ₙ 𝐻ₘ. In different combinations of interest, as steam combustion engine fuel, m varies from:

A. 1 to 26

B. 2 to 54

C. 2 to 26

D. 1 to 54

B. 2 to 54

The general chemical formula of a paraffin fuel is

A. 𝐶ₙ 𝐻₂ₙ

B. 𝐶ₙ 𝐻₂ₙ₋₆

C. 𝐶ₙ 𝐻₂ₙ₊₂

D. 𝐶ₙ 𝐻₂ₙ₋₂

C. 𝐶ₙ 𝐻₂ₙ₊₂

Naphthenes and olefins are types of hydrocarbons with chemical formula of:

A. 𝐶ₙ 𝐻₂ₙ

B. 𝐶ₙ 𝐻₂ₙ₋₆

C. 𝐶ₙ 𝐻₂ₙ₊₂

D. 𝐶ₙ 𝐻₂ₙ₋₂

A. 𝐶ₙ 𝐻₂ₙ

Which of the following types of hydrocarbons have chemical formula of 𝐶ₙ 𝐻₂ₙ₋₂?

A. diolefins

B. aromatics

C. asphaltics

D. paraffins

A. diolefins

Which of the following types of hydrocarbons have chemical formula of 𝐶ₙ 𝐻₂ₙ₋₄?

A. diolefins

B. aromatics

C. asphaltics

D. paraffins

C. asphaltics

What is the chemical formula of an aromatic type hydrocarbon fuels?

A. 𝐶ₙ 𝐻₂ₙ₋₆

B. 𝐶ₙ 𝐻₂ₙ₋₂

C. 𝐶ₙ 𝐻₂ₙ

D. 𝐶ₙ 𝐻₂ₙ₊₂

A. 𝐶ₙ 𝐻₂ₙ₋₆

At atmospheric condition, hydrocarbon molecules with a low number of carbon atoms, 1 to 4 are.

A. liquids

B. atomic

C. gases

D. light oils

C. gases

Hydrocarbons with 5 to 15 carbon atoms are:

A. more or less volatile light oils

B. referred to as heavy oils

C. mixtures of many kinds of hydrocarbons

D. commercial fuels

A. more or less volatile light oils

Hydrocarbons with 16 to 26 carbon atoms are referred to as:

A. light oils

B. heavy oils

C. commercial fuels

D. lubricating oils

B. heavy oils

In a four stroke engine if a valve opens 25° before B.D.C. and close 10° after T.D.C. the valve should be:

A. puppet valve

B. exhaust valve

C. inlet valve

D. spring valve

B. exhaust valve

In a hot wire anemometer the rate of heat loss from sensing element is a function of:

A. mass rate of flow

B. pressure

C. velocity of flow

D. all of the above

C. velocity of flow

Sticking valve

A. valve tappet clearance incorrect

B. valve springs of defective material

C. valve guides gummed

D. lubricating oil of poor quality

B. valve springs of defective material

Detonation of pinging noises is due to:

A. early timing of fuel injection

B. late timing of fuel injection

C. head of piston carbonized

D. valve springs weak or broken

B. late timing of fuel injection

The thermal efficiency of a dual cycle engine with fixed compression ratio and fixed quantity of heat and with increase in pressure ratio, will

A. increase

B. remain same

C. decrease

D. depends on other factors

A. increase

Scavenging efficiency of a four stroke diesel engine is

A. in the range 80 - 95 percent

B. in the range 60 - 80 percent

C. below 60 percent

D. between 95% and 100%

D. between 95% and 100%

Volumetric efficiency of a well designed engine may be in the range of:

A. 75 to 90 percent

B. 60 to 75 percent

C. 30 to 50 percent

D. below 30 percent

A. 75 to 90 percent

During idling in a compression ignition engine the air fuel ratio may be of the order of:

A. 30

B. 200

C. 150

D. 100

A. 30

Vapour lock is

A. lock of vaporization of fuel to atmospheric pressure

B. excess fuel supply to engine because of faster evaporation

C. complete or partial stoppage of fuel supply because of vaporization of fuel in supply steam

D. locking carburettor jets because of vapor pressure

C. complete or partial stoppage of fuel supply because of vaporization of fuel in supply steam

Flash point of liquids is the temperature at which:

A. the fuel emits vapors at rate which produces an inflammable mixture with air

B. the fuel spontaneously ignites

C. the fuel ignites with a clearly visible flash

D. the fuel ignites without a spark

A. the fuel emits vapors at rate which produces an inflammable mixture with air

The mean effective pressure of a diesel cycle have fixed compression ratio will increase if cut off ratio is:

A. increased

B. decreased

C. independent of compression ratio

D. depends on other factor

A. increased

Hot spots

A. do not exist in engines

B. are the hottest spot in the engine

C. are the spots where heavier functions of fuel vaporized

D. are the defects in S.I. in engines

C. are the spots where heavier functions of fuel vaporized

Flash point for diesel fuel oil should be:

A. maximum 49 ℃

B. maximum 490 ℃

C. maximum 200 ℃

D. maximum 300 ℃

A. maximum 49 ℃

Morse test is conducted on:

A. single - cylinder engines

B. multi - cylinder engines

C. horizontal engines

D. vertical engines

B. multi - cylinder engines

Prony brake is used for testing of:

A. small engines

B. large engines

C. engines having small flywheel

D. high speed engines

A. small engines

Clog point of an oil refer to:

A. the point of maximum contamination of oil

B. the level of impurities beyond which oil ceases to flow

C. the temperature at which oil solidifies

D. the temperature at which paraffin and waxes in oil start precipitating

D. the temperature at which paraffin and waxes in oil start precipitating

Otto cycle consists of:

A. two isentropic and two constant volumes processes

B. two isentropic and two constant pressure processes

C. two adiabatic and two isothermal processes

D. two isothermal and two constant volume processes

A. two isentropic and two constant volumes processes

Diesel cycle consist of:

A. isentropic, isothermal, constant volume constant pressure processes

B. two constant volume, one constant pressure, one isothermal process

C. two isentropic, one constant volume and one constant pressure processes

D. two constant pressure, one constant volume, and one isentropic processes

C. two isentropic, one constant volume and one constant pressure processes

Which is not correct for calculating air stand efficiency?

A. all processes are reversible

B. specific heat remains unchanged at temperature

C. no account of the mechanism of heat transfer considered

D. gases dissociate at higher temperatures

D. gases dissociate at higher temperatures

The king pin inclination is generally:

A. less than 0.5°

B. between 1° and 2°

C. between 2° and 5°

D. more than 9°

C. between 2° and 5°

For balancing single cylinder engine a counter weight is added to:

A. piston

B. piston pin

C. cam

D. crank

D. crank

To measure the clearance between the valve and tappet of an automobile engine we use a___________.

A. Vernier scale

B. feeler gauge

C. pneumatic gauge

D. slip gauge

B. feeler gauge

By supercharging:

A. power stroke becomes stronger

B. loss in exhaust gets reduced

C. engine can be made to run smoother

D. thermal efficiency of the engine can be improved

D. thermal efficiency of the engine can be improved

Speedometer drive is generally taken from:

A. dynamo

B. flywheel

C. fan belt

D. front wheel

D. front wheel

Odometer is:

A. an instrument that indicates the condition of battery

B. an instrument used for measurement of consumption

C. an instrument used for BHP measurement

D. an instrument used for distance measurement

D. an instrument used for distance measurement

Automobile radiator is filled with:

A. acidic water

B. alkaline water

C. hard water

D. soft water

D. soft water

The ignition coil acts as:

A. a capacitor

B. an inductor

C. an RC circuit

D. a step up transformer

D. a step up transformer

The self starting motor for automobile is a:

A. universal motor

B. DC shunt motor

C. DC series motor

D. synchronous motor

C. DC series motor

Starting motor current may be about

A. 0.15 A

B. 0.5 A

C. 5.1 A

D. 25 A

D. 25 A

As a rule before the piston are remove, it is essential to remove the:

A. gudgeon pin

B. circlip

C. piston rings

D. crank shaft

C. piston rings

Common causes for excessive oil consumption include:

A. heavy oil and light bearings

B. high speed and worn engine

C. short trips and cold weather

D. frequent oil changes

B. high speed and worn engine

The device that is used for reducing the exhaust noise is called_____________.

A. exhaust manifold

B. exhaust pipe

C. muffler

D. none of the above

C. muffler

The device that is used to measure the clearance between the valve and tappet of an internal combustion engine is measured by using:

A. snap gauge

B. slip gauge

C. feeler gauge

D. micrometer

C. feeler gauge

Which of the following instrument is used measuring specific gravity?

A. thermometer

B. hygrometer

C. anemometer

D. hydrometer

D. hydrometer

Exhaust gas leakage into the cooling system is likely to occur because of defective:

A. cylinder head gasket

B. manifold gasket

C. water pump

D. any of the above

A. cylinder head gasket