4791 + Mcqs in Mechanical Engineering Page 49 McqOptions

2401.	The throttling process is __________ process.
A.	reversible
B.	irreversible
C.	reversible or irreversible
Answer» C. reversible or irreversible

Discussion

2402.	First law of thermodynamics deals with
A.	conservation of heat
B.	conservation of momentum
C.	conservation of mass
D.	conservation of energy
Answer» E.

Discussion

2403.	It is impossible to transfer heat from a body at a lower temperature to a body at a higher temperature, without the aid of an external source.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

2404.	In S. I. units, the value of the universal gas constant is
A.	8.314 J/kg mole-K
B.	83.14 J/kgmole-K
C.	831.4 J/kgmole-K
D.	8314 J/kgmole-K
Answer» E.

Discussion

2405.	Which of the following is the extensive property of a thermodynamic system?
A.	Pressure
B.	Volume
C.	Temperature
D.	Density
Answer» C. Temperature

Discussion

2406.	Petrol is distilled at
A.	65 to 220 C
B.	220 to 345 C
C.	345 to 470 C
D.	470 to 550 C
Answer» B. 220 to 345 C

Discussion

2407.	If the carbon content in the bituminous coal is 78 to 81%, it is said to be coking bituminous coal.
A.	Agree
B.	Disagree
Answer» C.

Discussion

2408.	The workdone in a free expansion process is zero.
A.	True
B.	False
Answer» B. False

Discussion

2409.	When a system changes its state from one equilibrium state to another equilibrium state, then the path of successive states through which the system has passed, is known as
A.	thermodynamic law
B.	thermodynamic process
C.	thermodynamic cycle
D.	none of these
Answer» C. thermodynamic cycle

Discussion

2410.	The fuel mostly used in blast furnace for extracting pig iron from iron ores is
A.	hard coke
B.	soft coke
C.	pulverised coal
D.	bituminous coal
Answer» B. soft coke

Discussion

2411.	The ultimate analysis of coal consists of the determination of the percentage of
A.	carbon
B.	hydrogen and nitrogen
C.	sulphur and ash
D.	all of these
Answer» E.

Discussion

2412.	A cycle consisting of two constant pressure and two isentropic processes is known as
A.	Carnot cycle
B.	Stirling cycle
C.	Otto cycle
D.	none of these
Answer» E.

Discussion

2413.	The __________ states that change of internal energy of a perfect gas is directly proportional to the change of temperature.
A.	Boyle's law
B.	Charle's law
C.	Gay-Lussac law
D.	Joule's law
Answer» E.

Discussion

2414.	The heat energy stored in the gas and used for raising the temperature of the gas is known as
A.	external energy
B.	internal energy
C.	kinetic energy
D.	molecular energy
Answer» C. kinetic energy

Discussion

2415.	The change of entropy, when heat is removed from the gas, is positive.
A.	Yes
B.	No
Answer» C.

Discussion

2416.	A closed cycle gas turbine works on Joule's cycle.
A.	True
B.	False
Answer» B. False

Discussion

2417.	One kg of sulphur requires 1 kg of oxygen for complete combustion and produces 2 kg of sulphur dioxide.
A.	True
B.	False
Answer» B. False

Discussion

2418.	The change of entropy, when heat is absorbed by the gas, is
A.	positive
B.	negative
C.	positive or negative
Answer» B. negative

Discussion

2419.	A machine which violates the first law of thermodynamics is known as perpetual motion machine of the second kind.
A.	Correct
B.	Incorrect
Answer» C.

Discussion

2420.	In a reversible adiabatic process, the ratio of T1/T2 is equal to
A.	<img src="/_files/images/mechanical-engineering/thermodynamics/244-132-1.png">
B.	<img src="/_files/images/mechanical-engineering/thermodynamics/244-132-2.png">
C.	<img src="/_files/images/mechanical-engineering/thermodynamics/244-132-3.png">
D.	<img src="/_files/images/mechanical-engineering/thermodynamics/244-132-4.png">
Answer» C. <img src="/_files/images/mechanical-engineering/thermodynamics/244-132-3.png">

Discussion

2421.	Steam coal is a
A.	pulverised coal
B.	brown coal
C.	coking bituminous coal
D.	non-coking bituminous coal
Answer» E.

Discussion

2422.	Both the Ericsson and Joule's cycle have two constant pressure processes.
A.	True
B.	False
Answer» B. False

Discussion

2423.	The atomic mass of nitrogen is __________ oxygen.
A.	equal to
B.	less than
C.	more than
Answer» C. more than

Discussion

2424.	The universal gas constant (or molar constant) of a gas is the product of
A.	molecular mass of the gas and the gas constant
B.	atomic mass of the gas and the gas constant
C.	molecular mass of the gas and the specific heat at constant pressure
D.	molecular mass of the gas and the specific heat at constant volume
Answer» B. atomic mass of the gas and the gas constant

Discussion

2425.	A process, in which the working substance neither receives nor gives out heat to its surroundings during its expansion or compression, is called
A.	isothermal process
B.	hyperbolic process
C.	adiabatic process
D.	polytropic process
Answer» D. polytropic process

Discussion

2426.	The ideal efficiency of simple gas turbine cycle depends upon pressure ratio.
A.	Yes
B.	No
Answer» B. No

Discussion

2427.	The natural petroleum may be separated into
A.	petrol
B.	kerosene
C.	fuel oil
D.	lubricating oil
Answer» E.

Discussion

2428.	When gas is heated at constant pressure, the heat supplied is utilised in
A.	increasing the internal energy of gas
B.	doing some external work
C.	increasing the internal energy of gas and also for doing some external work
D.	none of the above
Answer» D. none of the above

Discussion

2429.	Second law of thermodynamics defines
A.	heat
B.	work
C.	internal energy
D.	entropy
Answer» E.

Discussion

2430.	Energy can neither be created nor destroyed, but it can be transformed from one form to another. This statement is known as
A.	Zeroth law of thermodynamics
B.	First law of thermodynamics
C.	Second law of thermodynamics
D.	Kinetic theory of gases
Answer» C. Second law of thermodynamics

Discussion

2431.	The efficiency of the Carnot cycle is (where T1 and T2 = Highest and lowest temperature during the cycle)
A.	<img src="/_files/images/mechanical-engineering/thermodynamics/248-180-1.png">
B.	<img src="/_files/images/mechanical-engineering/thermodynamics/248-180-2.png">
C.	<img src="/_files/images/mechanical-engineering/thermodynamics/248-180-3.png">
D.	<img src="/_files/images/mechanical-engineering/thermodynamics/248-180-4.png">
Answer» D. <img src="/_files/images/mechanical-engineering/thermodynamics/248-180-4.png">

Discussion

2432.	A definite area or a space where some thermodynamic process takes place is known as
A.	thermodynamic system
B.	thermodynamic cycle
C.	thermodynamic process
D.	thermodynamic law
Answer» B. thermodynamic cycle

Discussion

2433.	The amount of heat required to raise the temperature of __________ water through one degree is called kilojoule.
A.	1 g
B.	10 g
C.	100 g
D.	1000 g
Answer» E.

Discussion

2434.	The amount of heat required to raise the temperature of 1 kg of water through one Kelvin is called
A.	specific heat at constant volume
B.	specific heat at constant pressure
C.	kilo-Joule
D.	none of these
Answer» D. none of these

Discussion

2435.	When wood is heated with a limited supply of air to a temperature not less than 280 C, the resulting fuel is
A.	coke
B.	wood charcoal
C.	bituminous coal
D.	briquetted coal
Answer» C. bituminous coal

Discussion

2436.	The heating of a gas at constant pressure is governed by
A.	Boyle's law
B.	Charles' law
C.	Gay-Lussac law
D.	Avogadro's law
Answer» C. Gay-Lussac law

Discussion

2437.	Reversed Joule cycle is known as
A.	Carnot cycle
B.	Bell-Coleman cycle
C.	Rankine cycle
D.	Stirling cycle
Answer» C. Rankine cycle

Discussion

2438.	In an ideal gas turbine plant, it is assumed that the compression and expansion processes are
A.	isothermal
B.	isentropic
C.	polytropic
D.	none of these
Answer» C. polytropic

Discussion

2439.	The efficiency of Diesel cycle increases with increase in cut-off.
A.	Yes
B.	No
Answer» C.

Discussion

2440.	The property of a working substance which increases or decreases as the heat is supplied or removed in a reversible manner, is known as
A.	enthalpy
B.	internal energy
C.	entropy
D.	external energy
Answer» D. external energy

Discussion

2441.	It is __________ to make an engine working on a Carnot cycle.
A.	possible
B.	impossible
Answer» C.

Discussion

2442.	The process is adiabatic, if the value of n in the equation pvn = C, is
A.	0
B.	1
C.
D.
Answer» D.

Discussion

2443.	The ratio of root mean square velocity to average velocity of gas molecules at a particular temperature is
A.	0.086
B.	1.086
C.	3.086
D.	4.086
Answer» C. 3.086

Discussion

2444.	When coal is first dried and then crushed to a fine powder by pulverising machine, the resulting fuel is called
A.	wood charcoal
B.	bituminous coal
C.	briquetted coal
D.	none of these
Answer» E.

Discussion

2445.	Diesel cycle consists of __________ processes.
A.	two constant volume and two isentropic
B.	two constant pressure and two isentropic
C.	two constant volume and two isothermal
D.	one constant pressure, one constant volume and two isentropic
Answer» E.

Discussion

2446.	The efficiency of the dual combustion cycle for the same compression ratio, is __________ Diesel cycle.
A.	greater than
B.	less than
C.	equal to
Answer» B. less than

Discussion

2447.	The throttling process is an irreversible steady flow expansion process.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

2448.	Charles' law states that all perfect gases change in volume by __________ of its original volume at 0 C for every 1 C change in temperature, when pressure remains constant.
A.	1/27th
B.	1/93th
C.	1/173th
D.	1/273th
Answer» E.

Discussion

2449.	A close cycle gas turbine gives __________ efficiency as compared to an open cycle gas turbine.
A.	same
B.	lower
C.	higher
Answer» D.

Discussion

2450.	To ensure complete and rapid combustion of a fuel, some quantity of air, in excess of the theoretical or minimum air is supplied.
A.	Yes
B.	No
Answer» B. No

Discussion

Explore topic-wise MCQs in Engineering.

The throttling process is __________ process.

First law of thermodynamics deals with

It is impossible to transfer heat from a body at a lower temperature to a body at a higher temperature, without the aid of an external source.

In S. I. units, the value of the universal gas constant is

Which of the following is the extensive property of a thermodynamic system?

Petrol is distilled at

If the carbon content in the bituminous coal is 78 to 81%, it is said to be coking bituminous coal.

The workdone in a free expansion process is zero.

When a system changes its state from one equilibrium state to another equilibrium state, then the path of successive states through which the system has passed, is known as

The fuel mostly used in blast furnace for extracting pig iron from iron ores is

The ultimate analysis of coal consists of the determination of the percentage of

A cycle consisting of two constant pressure and two isentropic processes is known as

The __________ states that change of internal energy of a perfect gas is directly proportional to the change of temperature.

The heat energy stored in the gas and used for raising the temperature of the gas is known as

The change of entropy, when heat is removed from the gas, is positive.

A closed cycle gas turbine works on Joule's cycle.

One kg of sulphur requires 1 kg of oxygen for complete combustion and produces 2 kg of sulphur dioxide.

The change of entropy, when heat is absorbed by the gas, is

A machine which violates the first law of thermodynamics is known as perpetual motion machine of the second kind.

In a reversible adiabatic process, the ratio of T1/T2 is equal to

Steam coal is a

Both the Ericsson and Joule's cycle have two constant pressure processes.

The atomic mass of nitrogen is __________ oxygen.

The universal gas constant (or molar constant) of a gas is the product of

A process, in which the working substance neither receives nor gives out heat to its surroundings during its expansion or compression, is called

The ideal efficiency of simple gas turbine cycle depends upon pressure ratio.

The natural petroleum may be separated into

When gas is heated at constant pressure, the heat supplied is utilised in

Second law of thermodynamics defines

Energy can neither be created nor destroyed, but it can be transformed from one form to another. This statement is known as

The efficiency of the Carnot cycle is (where T1 and T2 = Highest and lowest temperature during the cycle)

A definite area or a space where some thermodynamic process takes place is known as

The amount of heat required to raise the temperature of __________ water through one degree is called kilojoule.

The amount of heat required to raise the temperature of 1 kg of water through one Kelvin is called

When wood is heated with a limited supply of air to a temperature not less than 280 C, the resulting fuel is

The heating of a gas at constant pressure is governed by

Reversed Joule cycle is known as

In an ideal gas turbine plant, it is assumed that the compression and expansion processes are

The efficiency of Diesel cycle increases with increase in cut-off.

The property of a working substance which increases or decreases as the heat is supplied or removed in a reversible manner, is known as

It is __________ to make an engine working on a Carnot cycle.

The process is adiabatic, if the value of n in the equation pvn = C, is

The ratio of root mean square velocity to average velocity of gas molecules at a particular temperature is

When coal is first dried and then crushed to a fine powder by pulverising machine, the resulting fuel is called

Diesel cycle consists of __________ processes.

The efficiency of the dual combustion cycle for the same compression ratio, is __________ Diesel cycle.

The throttling process is an irreversible steady flow expansion process.

Charles' law states that all perfect gases change in volume by __________ of its original volume at 0 C for every 1 C change in temperature, when pressure remains constant.

A close cycle gas turbine gives __________ efficiency as compared to an open cycle gas turbine.

To ensure complete and rapid combustion of a fuel, some quantity of air, in excess of the theoretical or minimum air is supplied.