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Quiz on GENERAL ENGINEERING II, created by shuree on 18/04/2015.

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GENERAL ENGINEERING II

Question 1 of 149

1

What type of bond exists predominantly in sodium chloride crystal ?

Select one of the following:

  • ionic bond

  • metallic bond

  • covalent bond

  • polar bond

Explanation

Question 2 of 149

1

Pure metal A undergoes an isothermal transformation in which its crystal structure changes from face centered cubic FCC to body centered cubic BCC. As a result, the volume of a piece of metal A

Select one of the following:

  • increased

  • decreased

  • remains the same

  • decreased up to the midpoint of the transformation and then asymptotically reaches its original value

Explanation

Question 3 of 149

1

Which of the following leads to a reduction in the electrical resistivity of a pure metal ?

Select one of the following:

  • annealing

  • cold working

  • grain refinement

  • addition of alloying elements

Explanation

Question 4 of 149

1

The rigidity of polymer can be increased by

Select one of the following:

  • all of these

  • increase in degree of polymerization

  • increase in the extent of cross linking

  • crystallization

Explanation

Question 5 of 149

1

Which of the following properties of a metal is insensitive to microstructure ?

Select one of the following:

  • modulus of elasticity

  • tensile strength

  • ductility

  • hardness

Explanation

Question 6 of 149

1

The dominant charge carriers in phosphorus - doped silicon crystal at room temperature are

Select one of the following:

  • electrons

  • electron holes

  • protons

  • silicon ions

Explanation

Question 7 of 149

1

Metals are conductive because

Select one of the following:

  • the electrons are loosely bound to the nuclei and therefore mobile

  • they have a characteristic metallic luster

  • they have extra electrons as exhibited by normally positive valence states

  • they are on the left side of the periodic table

Explanation

Question 8 of 149

1

An X - ray is

Select one of the following:

  • an electromagnetic radiation

  • a ray of electrons

  • a ray of helium nuclei

  • not known, hence the name " x " ray

Explanation

Question 9 of 149

1

An electron - volt is

Select one of the following:

  • a unit of energy equal to the energy possessed by an electron accelerating through a potential of one volt

  • a voltage unit commonly used when measuring the voltage of the electrons

  • the unit of electrical charge of one electron

  • none of the above

Explanation

Question 10 of 149

1

Group IA are easily ionized because

Select one of the following:

  • they have a single "s" electrons in the outer orbit

  • they are metals and therefore conductive

  • they react violently in water to liberate hydrogen

  • they have relatively low melting points for metal

Explanation

Question 11 of 149

1

The rare earth metals all have very similar chemical properties because :

Select one of the following:

  • successive members of the series are formed by adding 4f electrons which have little effect on the reactivity

  • they are rare, hence little is known about their chemistry

  • they melt at extreme temperatures, hence are nearly inert

  • they are in separate row at the bottom of the periodic table

Explanation

Question 12 of 149

1

Which of the following group of elements all form crystals of diamond structural lattice ?

Select one of the following:

  • carbon, silicon, germanium

  • carbon, boron, aluminum

  • carbon, cobalt, nickel

  • lithium, sodium, potassium

Explanation

Question 13 of 149

1

The stress or load where a crystalline material fails is usually less then the predicted from calculated bond strengths in the crystal lattice because

Select one of the following:

  • the strength of failure is governed by crystal defects or crystal bond strength

  • the stress at failure is not reproducible experimentally

  • plastic deformation occurs before failure

  • it is, to date, impossible to calculate something as complicated as the stress at failure

Explanation

Question 14 of 149

1

Which of the following material properties is adversely affected by grain refinement ?

Select one of the following:

  • creep resistance

  • tensile strength

  • ductility

  • elastic module

Explanation

Question 15 of 149

1

Which of the following classes of materials exhibit a decreasing electrical conductivity with increasing temperature ?

Select one of the following:

  • metals

  • pure ionic materials

  • intrinsic semiconductors

  • p - type semiconductors

Explanation

Question 16 of 149

1

The property that characterizes a material's ability to be drawn into a wire is its

Select one of the following:

  • ductility

  • tensile strength

  • fatigue endurance limit

  • impact strength

Explanation

Question 17 of 149

1

Which of the following treatments will result in an increase in the fatigue strength of steel ?

Select one of the following:

  • short peening

  • annealing

  • cold working

  • surface roughening

Explanation

Question 18 of 149

1

In p - type semiconductors, conductivity is provided by

Select one of the following:

  • the motion of holes

  • the motion of electrons

  • the motion of ions

  • the motion of conductivity

Explanation

Question 19 of 149

1

A photon is

Select one of the following:

  • a particle of electromagnetic radiation

  • a neutral proton

  • a neutral electron

  • a charge neutron

Explanation

Question 20 of 149

1

Isotopes of an element are atomic species with

Select one of the following:

  • the same number of protons and electrons , but different numbers of neutrons

  • the same number electrons , but different numbers of neutrons and protons

  • the same number protons , but different numbers of neutrons and electons

  • the same number of valence electrons , but different numbers of protons, neutrons and non - valence electrons

Explanation

Question 21 of 149

1

The separation of isotopes of an elements always requires a physical, rather than chemical separation because

Select one of the following:

  • the differences in isotopes show up as difference in physical properties

  • the atomic mass, a physical characteristic, constitutes the difference between the isotopes

  • the electron configuration and, hence, chemical reactivity are the same

  • all of the above

Explanation

Question 22 of 149

1

The electronic configuration, 1s² 2s² 2p⁶ 3s² 3p⁵ is that of

Select one of the following:

  • a halogen

  • an alkali metal

  • an inert gas

  • a transition metal

Explanation

Question 23 of 149

1

An angstrom unit, commonly used for atomic and sub - atomic distances is equal to

Select one of the following:

  • 10⁻¹⁰ m

  • 10¹⁰ m

  • 10⁻⁶ m

  • the distance light travels in 10⁻¹⁰ seconds

Explanation

Question 24 of 149

1

Which of the following statements about free carrier concentration associated with intrinsic semiconductors at room temperature is valid ?

Select one of the following:

  • it decreases with increasing values of energy gap

  • it increases with increasing values of energy gap

  • in increases with increasing carrier mobility

  • it decreases with increasing carrier mobility

Explanation

Question 25 of 149

1

At absolute zero temperature, all the valence electrons in an intrinsic semiconductor

Select one of the following:

  • are in the valence bond

  • are in the forbidden gap

  • are in the conduction bond

  • are free electrons

Explanation

Question 26 of 149

1

Carrier mobility depends on

Select one of the following:

  • temperature and the regularity of the crystal structure

  • resistivity

  • conductivity

  • charge per carrier

Explanation

Question 27 of 149

1

The movement of changers from an area of higher carrier concentration to an area of lower concentration is called

Select one of the following:

  • diffusion

  • gradient

  • mobility

  • recombination

Explanation

Question 28 of 149

1

Which term describes a material whose properties depend on the direction of stress

Select one of the following:

  • anisotropic

  • isotropic

  • endotropic

  • asymmetrical

Explanation

Question 29 of 149

1

Materials that emit light in the absence of high heat and continue to emit light after the energy source has been removed are called

Select one of the following:

  • phosphorescent

  • fluorescent

  • semiconductor - laser diodes

  • translucent diodes

Explanation

Question 30 of 149

1

A gamma ray is composed of

Select one of the following:

  • high energy electromagnetic radiation

  • high energy protons

  • high energy electrons

  • high energy neutrinos

Explanation

Question 31 of 149

1

Plank's constant represents

Select one of the following:

  • the ratio between the magnitude of a quantum of radiated energy and its frequency

  • the quantum or smallest amount of energy that can be emitted by radiation

  • the number of ergs in a kilogram calorie

  • the smallest number of any physical significance

Explanation

Question 32 of 149

1

The elements exhibit periodically recurring chemical and physical properties because

Select one of the following:

  • the properties are largely determined by the quantum numbers of the outer electrons, all of which except the first which indicates the orbit, recur in each orbit

  • they are arrange that way in the periodic table

  • the reason is unknown, it is simply observed experimentally

  • probability considerations dictate that properties will recur since there are limited number of possibilities

Explanation

Question 33 of 149

1

Which element about crystal dislocations is incorrect ?

Select one of the following:

  • dislocation in a crystalline lattice is located in an unexpected place

  • dislocations affect the tensile strength of a crystal

  • edge, screw and mixed dislocations are possible

  • dislocation is the defect caused by an atomic misalignment in a crystal

Explanation

Question 34 of 149

1

Ions are formed when

Select one of the following:

  • all of these

  • electrons are displaced from atoms or molecules by bombardment of high energy particles

  • a salt forms in an acid base neutralization reaction

  • salt crystal forms from the reaction of elemental sodium and chlorine

Explanation

Question 35 of 149

1

Which of the following statements about two crystalline forms of carbon, graphite and diamond is not correct ?

Select one of the following:

  • the properties of two crystals are, in fact, more similar than dissimilar

  • the diamond lattice is transparent to visible light, graphite is not

  • diamond is the hardest naturally occurring substance, graphite is soft

  • at high temperature diamond is a semiconductor, graphite is a conductor

Explanation

Question 36 of 149

1

Avogadro's number represents

Select one of the following:

  • the number of molecules in one gram mole of any compound

  • the number of molecules in one gram of any compound

  • the number of molecules in one liter of any gas at 1 atm pressure and 0°C

  • the number of valence electrons in a mole of any element

Explanation

Question 37 of 149

1

Aluminum hydroxide Al(OH)₃ is called an amphoteric hydroxide because

Select one of the following:

  • it can react as either an acid or a base

  • it has limited solubility in water

  • it contains 3 hydroxyl groups

  • either one, two or three hydroxyl group can ionize in water

Explanation

Question 38 of 149

1

Which of the following characteristics of the alkaline earth elements is unique

Select one of the following:

  • they are in group IIA of the periodic table

  • they have two "s" electrons in the outer orbit

  • they exhibit a valence of +2

  • they are found in soil

Explanation

Question 39 of 149

1

The chemical formula of the salt formed from the neutralization of potassium hydroxide and sulphuric acid is

Select one of the following:

  • K₂SO₄

  • NaCl

  • P₂SO₄

  • KSO₄

Explanation

Question 40 of 149

1

The chemical formula of the most common compound formed from beryllium and iodine is

Select one of the following:

  • BeI₂

  • Be₂I₇

  • BeI

  • Be₇I₂

Explanation

Question 41 of 149

1

Which of the following statements about the halogens is incorrect ?

Select one of the following:

  • they will react with water to form very strong bases

  • they are good oxidizing agents

  • they all exhibit a valence of -1

  • they form diatomic molecules

Explanation

Question 42 of 149

1

The group VIII elements, called the noble or rare gases, have the following properties

Select one of the following:

  • they do not react with other elements

  • they are rare

  • they are lighter than air

  • they remain gaseous down to just few degrees above absolute zero

Explanation

Question 43 of 149

1

Many transition metals exhibit more than one valence state in simple chemical reaction because

Select one of the following:

  • d electrons from one orbital down are not as reactive as the s electrons in the outer orbit

  • s and p electrons in the same orbit have very different reactivities

  • the valence state of metals change of the other elements in the molecule change

  • it is not always possible to predict how even simple reactions will occur

Explanation

Question 44 of 149

1

For this reaction, the equilibrium conditions are
H₂ + I₂ = 2HI ΔH = -7.9 KJ

Select one of the following:

  • temperature and concentration

  • pressure, temperature and concentration

  • pressure only

  • temperature only

Explanation

Question 45 of 149

1

Ammonia is prepared by Haber's process
N₂ + 3H₂ = 2NH₃ ΔH = -5.3 KJ
In order to maximize the yield of ammonia, one can:

Select one of the following:

  • increase concentrations of hydrogen and nitrogen and decrease the temperature

  • increase concentrations of hydrogen and nitrogen and increase the temperature

  • decrease concentrations of hydrogen and nitrogen and increase the temperature

  • increase the concentrations of all the gases and increase the temperature

Explanation

Question 46 of 149

1

A close system experiences a reversible process where heat rejection is the only energy transfer. The entropy change

Select one of the following:

  • must be negative

  • must be zero

  • must be positive

  • is equal to the heat transfer

Explanation

Question 47 of 149

1

Consider an air - water vapor mixture similar to the atmosphere. If the dry bulb temperature equals the dew point temperature, the relative humidity will be

Select one of the following:

  • 100 %

  • 25 %

  • 0 %

  • 50 %

Explanation

Question 48 of 149

1

If the temperature of a medium is 0°C, what will be the temperature if it is doubled ?

Select one of the following:

  • 273°C

  • 0°C

  • 524°R

  • 460°R

Explanation

Question 49 of 149

1

The compression ignition cycle is modeled by which ideal cycle ?

Select one of the following:

  • diesel cycle

  • otto cycle

  • rankine cycle

  • brayton cycle

Explanation

Question 50 of 149

1

An ideal gas is contained in a rigid container. There is no work of a rotating shaft associated with the container. Any heat transfer is a function of

Select one of the following:

  • temperature only

  • pressure only

  • volume only

  • there cannot be any heat transfer

Explanation

Question 51 of 149

1

In a combustion chamber, fuel is burned to raise the temperature of the medium prior to production of work through an expansion process. The heat generated during the combustion reaction is the

Select one of the following:

  • heat of reaction

  • specific heat

  • heat of vaporization

  • heat of formation

Explanation

Question 52 of 149

1

There are many types of work associated with energy transfer across a boundary. One form of work is flow work which is described by all of the following except

Select one of the following:

  • it is associated with a closed system

  • it is the work which pushes mass in or out of a device

  • it is necessary to maintain a continuous flow

  • it is added to the internal energy to obtain enthalpy in the first law for a control volume

Explanation

Question 53 of 149

1

An open system First Law should be utilized for all of the following except

Select one of the following:

  • a piston - cylinder device

  • a nozzle

  • a turbine

  • a compressor

Explanation

Question 54 of 149

1

An insulated rigid container contains and ideal gas. The container is initially divided in half by a membrane such that one side is a vacuum and the other side contains the ideal gas. The membrane is broken and the gas fills the entire volume. All are true except

Select one of the following:

  • the temperature is quadrupled

  • the pressure is halved

  • the volume is doubled

  • the process is irreversible

Explanation

Question 55 of 149

1

An adiabatic process is characterized by which of the following ?

Select one of the following:

  • the heat transfer is zero

  • the entropy change is zero

  • the work is zero

  • it is reversible

Explanation

Question 56 of 149

1

A rigid container is heated by the sun. There is no shaft work associated with the container. From the First Law of Thermodynamics, you determine the resulting work to be

Select one of the following:

  • equal to zero

  • equal to the heat transter

  • equal to the volume times the change in pressure

  • equal to the change in internal energy

Explanation

Question 57 of 149

1

An inventor claims to have built and engineer which will revolutionize the automotive industry. Which of the following would be the best test to determine if the inventors claim is true ?

Select one of the following:

  • second law of thermodynamics

  • conservation of mass

  • first law of thermodynamics

  • zeroth law of thermodynamics

Explanation

Question 58 of 149

1

The isentropic efficiency is used to compare actual device such as turbines, compressors, nozzle and diffusers to ideal ones. Which statement is true

Select one of the following:

  • the inlet state and exit pressure are the same for both the ideal and actual device

  • only the ideal device is considered adiabatic

  • the ideal device operate irreversibly

  • the efficiency can be greater than one

Explanation

Question 59 of 149

1

The steam power cycle is modeled by the ideal cycle known as the

Select one of the following:

  • rankine cycle

  • otto cycle

  • diesel cycle

  • brayton cycle

Explanation

Question 60 of 149

1

In an ideal refrigeration cycle, liquid leaves the condenser and is expanded in such a manner that the enthalpy of the resulting saturated mixture. This type of expansion is known as

Select one of the following:

  • throttling process

  • an isothermal process

  • a compression process

  • an isochoric process

Explanation

Question 61 of 149

1

In the case of regenerative gas turbine engine, which of the following is false ?

Select one of the following:

  • there is no heat rejected to the atmosphere in a regenerative gas turbine engine

  • the regenerator improves the efficiency of the engine

  • the exit temperature of the generator is higher than the inlet temperature of the compressor

  • if the generator is reversible, the effectiveness can approach 100 %

Explanation

Question 62 of 149

1

For an ideal turbojet, all of the following statements are true except

Select one of the following:

  • the work produced by the turbine is greater than the work required by the compressor

  • the process efficiency of the turbine is 100 %

  • the process efficiency of the compressor is 100 %

  • the process efficiency of the nozzle is 100 %

Explanation

Question 63 of 149

1

Which of the following statements about the carnot efficiency is not true ?

Select one of the following:

  • no reversible power cycles operating between two thermal reservoir can have an efficiency equal to the carnot efficiency

  • it depends only on the temperatures of the thermal reservoir

  • it can be used to determine if the cycle is possible or impossible

  • absolute temperature scales must be used when performing carnot efficiency calculation

Explanation

Question 64 of 149

1

Two independent intensive properties are required to fix the state of pure, simple compressible substance. People only attempt to fix the state of the medium using heat and work, which are not properties, which of the following statements about heat and work is not true ?

Select one of the following:

  • heat and work are point function

  • heat and work are transient phenomena

  • heat and work are forms of energy

  • heat and work are boundary phenomena

Explanation

Question 65 of 149

1

For steady, incompressible, inviscid flow, with no shaft and heat transfer, Bernoulli's equation can be written P/ρ + ½ v² + gz = constant. This form of equation is valid

Select one of the following:

  • for rotational flow, but only along streamlines

  • for irrotational flow, but only along streamlines

  • for rotational flow everywhere

  • for rotational flow, but only across streamlines

Explanation

Question 66 of 149

1

The simplified continuity equation ∇V = 0 is not valid for

Select one of the following:

  • steady compressible flow

  • steady incompressible flow

  • unsteady incompressible flow

  • steady rotational incompressible flow

Explanation

Question 67 of 149

1

How many electrons are there in the outermost octate of a chlorine atom ?

Select one of the following:

  • 7

  • 1

  • 3

  • 8

Explanation

Question 68 of 149

1

Heat transferred at constant volume process to the thermodynamic system of a fixed mass. The thermodynamic system will produce

Select one of the following:

  • zero work

  • small amount of work

  • negative work

  • positive work

Explanation

Question 69 of 149

1

Compressibility factor Z is a measure of the deviation of the actual gas behavior from ideal gas. An actual gas behavior may be assumed closed to the ideal gas when compressiblity factor Z approaches

Select one of the following:

  • 1.0

  • 0

  • 0.5

  • 0.75

Explanation

Question 70 of 149

1

Let's assume that the gas can be heated either at constant pressure or at constant volume process. The amount of heat Qp and Qv are transferred to the gas accordingly. If temperature increment per unit mass ΔT = constant, then

Select one of the following:

  • Qp is greater than Qv

  • Qp = Qv

  • Qp is less than Qv

  • Qp = Qv - ΔU

Explanation

Question 71 of 149

1

In manufacturing process 1000 KW of waste heat at temperature 327°C is available for utilization purposes. If the ambient temperature is 27°C, the designed heat engine producing 510 KW of net power will be

Select one of the following:

  • impossible

  • possible

  • irreversible

  • reversible

Explanation

Question 72 of 149

1

Which of the following instruments for measuring fluid velocity does not need to be calibrated ?

Select one of the following:

  • pitot static tube

  • orifice meter

  • venture tube

  • weir

Explanation

Question 73 of 149

1

Capillarity or the rise or fall of liquid in a thin tube is primarily controlled by which fluid property ?

Select one of the following:

  • surface tension

  • viscosity

  • density

  • temperature

Explanation

Question 74 of 149

1

A polytropic process is one in which the functional relationship between pressure and volume is given by PV ᴺ = constant with N value from -∞ to +∞ depending on the particular process. A constant volume process is represented by N equals

Select one of the following:

  • zero

  • 2

  • K

Explanation

Question 75 of 149

1

Cavitation in fluid mechanics refers to

Select one of the following:

  • a liquid to gaseous phase transition of the fluid due to low pressure

  • the oscillation of a plate due to turbulent fluctuations

  • the condensation of the vapor into liquid due to high pressure

  • the violation of the no slip condition on the wall

Explanation

Question 76 of 149

1

A large class of devices involve work. Assuming reversible steady state, steady flow process with negligible changes in kinetic and potential energy, the elementary work is

Select one of the following:

  • - Vdp

  • pdV

  • Vdp + pdV

  • Vdp - pdV

Explanation

Question 77 of 149

1

The reheat rankine cycle is proposed to decrease

Select one of the following:

  • moisture content in the low pressure stages of the turbine

  • mass flow rate of cooling water in the condenser

  • back pressure of the turbine

  • volumetric flow rate of the working fluid

Explanation

Question 78 of 149

1

In compressible fluid mechanics, a shock wave is considered normal shock wave when

Select one of the following:

  • the angle between the direction of flow and the wave is 90°

  • the shock wave occurs in air

  • the shock wave occurs at oblique angle to the flow

  • the flow remains supersonic on both sides of the shock wave

Explanation

Question 79 of 149

1

Which of the following statements defines best the capitalized cost ?

Select one of the following:

  • is the present worth of a specified uniform cash flow for an infinite analysis period

  • it is the initial cost of some equipment

  • it is the salvage value of an equipment

  • it is the amount of money equal to the cost minus benefit for an equipment

Explanation

Question 80 of 149

1

Which of the following is not taken into account in making an economic decision between two alternative equipment ?

Select one of the following:

  • reliability

  • operating cost

  • rate of return

  • salvage value

Explanation

Question 81 of 149

1

A heat sink will dissipate heat energy more rapidly if

Select one of the following:

  • its surface area is increased

  • its temperature is the same as the temperature of the surrounding air

  • it is covered by a material having a high thermal resistance

  • it is kept away from air current

Explanation

Question 82 of 149

1

A reference frame which remains fixed while fluid flows through is called

Select one of the following:

  • Eulerian

  • Lagrangian

  • Stokesian

  • A Navier - Stokes reference frame

Explanation

Question 83 of 149

1

For steady incompressible fully developed flow in a constant area pipe, friction along the walls of the pipe causes.

Select one of the following:

  • a reduction in static pressure along the length of the pipe

  • a reduction in mass flow rate along the length of pipe

  • a reduction of velocity along the length of pipe

  • an increase in the darcy friction factor along the length of the pipe

Explanation

Question 84 of 149

1

Select the answer which correctly ranks fluid meters from lowest to highest pressure loss

Select one of the following:

  • venturi tube, flow nozzle, thin plate orifice

  • venturi tube,thin plate orifice, flow nozzle

  • thin plate orifice, venturi tube, flow nozzle

  • flow nozzle, thin plate orifice, venturi tube

Explanation

Question 85 of 149

1

Identify which of the following problems for which the Moody chart would not be of use

Select one of the following:

  • flow in subsonic diffuser

  • flow of natural gas in long pipe

  • flow of oil in a long channel with square cross section

  • flow of water in a pipe at very high speed where the flow is extremely turbulent

Explanation

Question 86 of 149

1

Effective interest rate per year is defined as

Select one of the following:

  • the annual interest rate taking into account the effect of any compounding during the year

  • the nominal interest rate per year

  • the rate of return that can be realized from an investment

  • the interest rate per period times the number of periods per year

Explanation

Question 87 of 149

1

During inflationary time, which of the following statements best describes the best the loan payments of a fixed amount ?

Select one of the following:

  • future payments in year zero dollars are not constant in amount

  • future payments are worth more in year zero dollars

  • in actual dollars, the amount of future payments decreases

  • year zero dollars are worth less then future dollars

Explanation

Question 88 of 149

1

A pump is used to increase the pressure of water entering the boiler of steam power cycle. Which statement is true concerning the pump ?

Select one of the following:

  • the enthalpy of water leaving the pump is higher than the enthalpy of water entering the pump

  • the pump produces work

  • the pump has no effect on the cycle

  • the enthalpy is constant during the process

Explanation

Question 89 of 149

1

Which of the following is not a unit of pressure ?

Select one of the following:

  • kg / m²

  • Pa

  • bars

  • N / m²

Explanation

Question 90 of 149

1

Which of the following is the definition of Joule ?

Select one of the following:

  • N - m

  • a unit of power

  • kg - m / s²

  • rate of change of energy

Explanation

Question 91 of 149

1

Which of the following relations defines enthalpy ?

Select one of the following:

  • H = U + PV

  • H = U + P / T

  • H = U + P / V

  • H = PV + T

Explanation

Question 92 of 149

1

How is the quality x of a liquid vapor mixture defined ?

Select one of the following:

  • the fraction of the total mass that is saturated vapor

  • the fraction of the total volume that is saturated vapor

  • the fraction of total volume that is saturated liquid

  • the fraction of the total mass that is saturated liquid

Explanation

Question 93 of 149

1

What is the actual shape of the methane CH₄ molecule ?

Select one of the following:

  • a tetrahedral

  • linear

  • square planar

  • pyramidal

Explanation

Question 94 of 149

1

What is the oxidation state of the nitrogen in NO₃⁻ ?

Select one of the following:

  • + 5

  • - 1

  • + 3

  • + 1

Explanation

Question 95 of 149

1

What is the oxidation number of Cr in the dicromate ion (Cr₂O₇) ²⁻

Select one of the following:

  • + 6

  • - 1

  • 0

  • 7

Explanation

Question 96 of 149

1

Reactions generally proceed faster at higher temperature because of which of the following ?

Select one of the following:

  • the activation energy is less

  • the molecules are less energetic

  • the bonds are easier to break

  • the molecules collide more frequently

Explanation

Question 97 of 149

1

Determine the height of the centroid of the semi - circle with radius r from its diameter

Select one of the following:

  • 4r / 3π

  • 2r / 3

  • 2πr /3

  • 3r / 4π

Explanation

Question 98 of 149

1

What are valence electrons ?

Select one of the following:

  • the outer shell electrons

  • electrons with positive charge

  • the electrons of complete quantum shells

  • the K - quantum shell electrons

Explanation

Question 99 of 149

1

What is the strong bond between hydrogen atoms known as ?

Select one of the following:

  • covalent bond

  • ionic bond

  • metallic bond

  • ionic and metallic bond

Explanation

Question 100 of 149

1

What are Van der Waals forces ?

Select one of the following:

  • weak secondary bonds between atoms

  • primary bonds between atoms

  • forces between electrons and protons

  • forces present only in gases

Explanation

Question 101 of 149

1

Compare the metallic iron form Fe and the ferric ions Fe²⁺ and Fe³⁺. Which has the smallest atomic radius of the same temperature ?

Select one of the following:

  • Fe³⁺

  • Fe²⁺

  • Fe

  • they have the same radii

Explanation

Question 102 of 149

1

Polymers that favor crystallization are least likely to have which of the following

Select one of the following:

  • an atactic configuration of side group

  • small side group

  • only one repeating unit

  • small chain length

Explanation

Question 103 of 149

1

In general, what are the effects of cold working a metal ?

Select one of the following:

  • increase strength, decrease ductility

  • increase strength, increase ductility

  • decrease strength, decrease ductility

  • decrease strength, increase ductility

Explanation

Question 104 of 149

1

Which of the following is not structural class steel ?

Select one of the following:

  • tool and die

  • carbon

  • stainless

  • low - alloy

Explanation

Question 105 of 149

1

Which of the following phases of steel has face - centered cubic structure ?

Select one of the following:

  • austenite

  • ferrite

  • pearlite

  • martensite

Explanation

Question 106 of 149

1

The state of a thermodynamic system is always defined by its

Select one of the following:

  • properties

  • absolute temperature

  • process

  • temperature and pressure

Explanation

Question 107 of 149

1

Mathematically, a thermodynamic property is which of the following ?

Select one of the following:

  • a point function

  • a path function

  • an exact differential

  • discontinuous

Explanation

Question 108 of 149

1

The first law of thermodynamics states that

Select one of the following:

  • energy can neither be created nor destroyed

  • heat energy cannot be completely transformed into work

  • internal energy is due to molecular motion

  • entropy of the universe is increased by irreversible process

Explanation

Question 109 of 149

1

In terms of QH and QL, the network of a carnot cycle is

Select one of the following:

  • W = QH - QL

  • W = QH - QL / QL

  • W = QL / QH - QL

  • W = QL - QH

Explanation

Question 110 of 149

1

Is any non - quasistatic thermodynamic process, the over - all entropy of an isolated system will

Select one of the following:

  • increase only

  • decrease only

  • stay the same

  • decrease and then increase

Explanation

Question 111 of 149

1

Entropy is the measure of

Select one of the following:

  • randomness or disorder

  • the change in enthalpy of the system

  • the internal energy of the gas

  • the heat capacity of the substance

Explanation

Question 112 of 149

1

For spontaneously occurring natural process in an isolated system, which expression best express dS ?

Select one of the following:

  • dS is greater than 0

  • dS equals 0

  • dS is less than zero

  • dS = dQ / T

Explanation

Question 113 of 149

1

Energy changes are represented by all except

Select one of the following:

  • dQ rev / T

  • negative integral of VdP

  • mCpdT

  • TdS - PdV

Explanation

Question 114 of 149

1

Work or energy can be a function of all of the following except

Select one of the following:

  • force and time

  • force and distance

  • toque and angular acceleration

  • power and time

Explanation

Question 115 of 149

1

U + PV is a quantity called

Select one of the following:

  • enthalpy

  • flow energy

  • shaft work

  • entropy

Explanation

Question 116 of 149

1

In flow process, neglecting KE and PE changes, negative integral of Vdp represents

Select one of the following:

  • shaft work

  • heat transfer

  • closed system work

  • flow energy

Explanation

Question 117 of 149

1

Power may be expressed in units of

Select one of the following:

  • BTU / hr

  • ft - lbs

  • HP - hours

  • KW - hours

Explanation

Question 118 of 149

1

Equilibrium condition exist in all except which of the following ?

Select one of the following:

  • in steady state flow process

  • in reversible process

  • in process where driving forces are infinitesimals

  • where nothing can occur without an effect on the system's surroundings

Explanation

Question 119 of 149

1

Name the process that has no heat transfer

Select one of the following:

  • isentropic

  • isothermal

  • quasistatic

  • polytropic

Explanation

Question 120 of 149

1

An ideal gas ( k = 1.4 ) is expanded in a nozzle from Po = 1.5 MPa, To = 150°C, Vo = 0, to P₂ = 0.3 MPa. Assuming reversible adiabatic process the nozzle should be

Select one of the following:

  • convergent - divergent

  • diverging

  • converging

  • constant cross section

Explanation

Question 121 of 149

1

Enthalpy of an ideal gas is a function only of

Select one of the following:

  • temperature

  • entropy

  • pressure

  • internal energy

Explanation

Question 122 of 149

1

A small plastic bag is filled with moist air at 50% relative humidity, sealed and placed in an environmental chamber whose temperature and pressure may be independently varied. The relative humidity of the bag will lower under which of the following conditions

Select one of the following:

  • pressure is decreased

  • pressure is increased

  • temperature is decrease

  • temperature is decreased and pressure in increased

Explanation

Question 123 of 149

1

The rate of heat transfer through a given section of a uniform wall or a given temperature difference is

Select one of the following:

  • directly proportional to the thermal conductivity and inversely proportional to the thickness of the wall

  • directly proportional to the thermal conductivity and to the thickness of the wall

  • inversely proportional to the thermal conductivity and directly proportional thickness of the wall

  • inversely proportional to the thermal conductivity and to the thickness of the wall

Explanation

Question 124 of 149

1

Which of the following metals has the highest specific heat capacity at 100°C ?

Select one of the following:

  • aluminum

  • bismuth

  • copper

  • iron

Explanation

Question 125 of 149

1

The radical ion (NO₂)⁻ is called

Select one of the following:

  • nitrite

  • nitrate

  • nitride

  • binitrite

Explanation

Question 126 of 149

1

a sample of a substance to which chemical formula can be assigned, whose weight is equal to its formula weight is termed as

Select one of the following:

  • mole

  • molecule

  • gram equivalent weight

  • atom

Explanation

Question 127 of 149

1

The number of molecules in 22.4 L of a substance in its gaseous state is called

Select one of the following:

  • Avogadro's number

  • Dulong's number

  • Petit's number

  • Graham's number

Explanation

Question 128 of 149

1

Which of the following radioactive decay results in an increased Z or number of protons in the nucleus ?

Select one of the following:

  • negative beta decay ( electron emission )

  • alpha decay ( helium nucleus emission )

  • positive beta decay ( positron emission )

  • gamma emission ( photon energy emission )

Explanation

Question 129 of 149

1

The relationship between the extension of a spring and the force required to produce the extension is

Select one of the following:

  • F = kx

  • F = ma

  • F = μN

  • F = mv² / r

Explanation

Question 130 of 149

1

The deflection of beam is

Select one of the following:

  • inversely proportional to the modulus of elasticity and the moment of inertia

  • directly proportional to the modulus of elasticity and the moment of inertia

  • inversely proportional to the modulus of elasticity and the length of the beam cube

  • inversely proportional to the weight and length

Explanation

Question 131 of 149

1

Hard water is water which contains soluble salts of which of the following

Select one of the following:

  • calcium

  • sodium

  • sulfur

  • chlorine

Explanation

Question 132 of 149

1

A homogeneous round bar of diameter D, length L and total weight W is hung vertically from one end. If E is the modulus of elasticity, what is the total elongation of the bar ?

Select one of the following:

  • 2WL / πD²E

  • WL / πD²E

  • WL / 2πD²E

  • WL / 2E

Explanation

Question 133 of 149

1

A thin walled pressurized vessel consist of a right circular cylinder with flat ends. Midway between the ends the stress is greatest in what direction ?

Select one of the following:

  • circumferential

  • longitudinal

  • radial

  • at an angle of 45° to the longitudinal and circumferential directions

Explanation

Question 134 of 149

1

The stress concentration factor

Select one of the following:

  • is the ratio of the maximum stress produced in a cross section to the allowable stress

  • is the ratio of the average stress produced in a cross section to the allowable stress

  • is the ratio of areas involved in the sudden change in cross section

  • cannot be evaluated for brittle material

Explanation

Question 135 of 149

1

Poisson's ratio is the ratio of

Select one of the following:

  • unit lateral deformation to the unit of longitudinal deformation

  • unit stress to unit strain

  • elastic limit to proportional limit

  • shear strain to compressive strain

Explanation

Question 136 of 149

1

The modulus of rigidity of a steel member is

Select one of the following:

  • defined as the unit shear stress divided by the unit shear deformation

  • a function of the length and depth

  • equal to the modulus of elasticity divided by one Poise

  • defined as the length divided by the moment of inertia

Explanation

Question 137 of 149

1

A thin homogeneous metallic plate containing a hole is heated sufficiently to cause expansion. If the coefficient of surface expansion is linear, the area of the hole will

Select one of the following:

  • increase at the same rate as the area of the metal increases

  • decrease at the same rate as the area of the metal increases

  • stay the same

  • increase at twice the rate of the are of the metal increases

Explanation

Question 138 of 149

1

Hooke's law for an isotropic homogeneous medium experiencing one dimensional stress is

Select one of the following:

  • stress = E ⋅ strain

  • strain = E ⋅ stress

  • strain energy = E ⋅ internal energy

  • Force ⋅ area = E ⋅ change in length / length

Explanation

Question 139 of 149

1

The three moment equation may be used to analyze

Select one of the following:

  • continuous beam

  • beam loaded at the third point

  • a three element composite beam

  • a step tapered column

Explanation

Question 140 of 149

1

The area of the shear diagram of a beam between any two points on the beam is equal to the

Select one of the following:

  • change in the moment between the two points

  • change in the shear between the two points

  • total shear beyond the two points

  • average moment between the two points

Explanation

Question 141 of 149

1

Fixing both ends of a simply supported beam that has only a concentrated load at midspan will increase the allowed load by

Select one of the following:

  • 100 %

  • 50 %

  • 25 %

  • no change

Explanation

Question 142 of 149

1

Young's modulus of elasticity for a material can be calculated indirectly form which of the following properties of material ?

Select one of the following:

  • density and velocity of sound in the material

  • temperature coefficient of expansion and dielectric constant

  • temperature coefficient of expansion and specific heat

  • density and interatomic spacing in the material

Explanation

Question 143 of 149

1

Modulus of resilience is

Select one of the following:

  • the measure of a materials ability to store strain energy

  • the same as the modulus of elasticity

  • the reciprocal of the modulus of elasticity

  • a measure of the deflection of a member

Explanation

Question 144 of 149

1

When a metal is cold worked, all of the following generally occur except

Select one of the following:

  • grains become equi - axed

  • ductility increases

  • tensile strength increases

  • recrystallization temperature decreases

Explanation

Question 145 of 149

1

Instrinsic silicon becomes extrinsically conductive, with electrons as majority carriers, when doped with

Select one of the following:

  • antimony

  • boron

  • germanium

  • aluminum

Explanation

Question 146 of 149

1

Steel can be strengthened by the following except

Select one of the following:

  • annealing

  • quenching and tempering

  • work hardening

  • grain refinement

Explanation

Question 147 of 149

1

If 1080 steel ( 0.8 % wt C ) is annealed by very slow cooling from 1000°C to ambient temperature, its microstructure will consist of almost solely of

Select one of the following:

  • pearlite

  • austenite

  • bainite

  • cementite

Explanation

Question 148 of 149

1

Which of the following is not a method of non destructive testing of steel castings and forgings ?

Select one of the following:

  • chemical analysis

  • radiography

  • magnetic particles

  • ultrasonic

Explanation

Question 149 of 149

1

Compressive strength of fully cured concrete is most directly related to

Select one of the following:

  • water - cement ratio

  • sand gravel ratio

  • fineness modulus

  • aggregate gradation

Explanation