The compression ratio for Diesel engines is  A. 3 to 6  B. 5 to 8  C. 15 to 20  D. 20 to 30

The compression ratio for Diesel engines is  A. 3 to 6  B. 5 to 8  C. 15 to 20  D. 20 to 30
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The compression ratio for petrol engines is  A.3 to 6  B.5 to 8  C.15 to 20  D.20 to 30

Description : The compression ratio for petrol engines is  A.3 to 6  B.5 to 8  C.15 to 20  D.20 to 30

Last Answer : Answer: B

The efficiency of Diesel cycle depends upon  A. temperature limits  B. pressure ratio  C. compression ratio  D. cut-off ratio and compression ratio

Description : The efficiency of Diesel cycle depends upon  A. temperature limits  B. pressure ratio  C. compression ratio  D. cut-off ratio and compression ratio

Last Answer : Answer: D

Otto cycle efficiency is higher than Diesel cycle efficiency for the same compression ratio and heat input because in Otto cycle  A. combustion is at constant volume  B. expansion and compression are isentropic  C. maximum temperature is higher  D. heat rejection is lower

Description : Otto cycle efficiency is higher than Diesel cycle efficiency for the same compression ratio and heat input because in Otto cycle  A. combustion is at constant volume  B. expansion and compression are isentropic  C. maximum temperature is higher  D. heat rejection is lower

Last Answer : Answer: D

For same compression ratio and for same heat added  (a) Otto cycle is more efficient than Diesel cycle  (b) Diesel cycle is more efficient than Otto cycle  (c) efficiency depends on other factors  (d) both Otto and Diesel cycles are equally efficient  (e) none of the above.

Description : For same compression ratio and for same heat added  (a) Otto cycle is more efficient than Diesel cycle  (b) Diesel cycle is more efficient than Otto cycle  (c) efficiency depends on other factors  (d) both Otto and Diesel cycles are equally efficient  (e) none of the above.

Last Answer : Answer : a

Which of the following engines was introduced by a German engineer, Nickolas Otto?  a. Gasoline engine  b. Diesel engine  c. Gas turbine  d. Thermal engine

Description : Which of the following engines was introduced by a German engineer, Nickolas Otto?  a. Gasoline engine  b. Diesel engine  c. Gas turbine  d. Thermal engine

Last Answer : Gasoline engine

Which of the following engines is the most efficient?  a. Gas turbine  b. Diesel engine  c. Carnot engine  d. Gasoline engine

Description : Which of the following engines is the most efficient?  a. Gas turbine  b. Diesel engine  c. Carnot engine  d. Gasoline engine

Last Answer : Carnot engine

Which of the following best describes both Stirling and Ericson engines?  a. Internal combustion engine  b. External combustion engine  c. Diesel cycle  d. Rankine cycle

Description : Which of the following best describes both Stirling and Ericson engines?  a. Internal combustion engine  b. External combustion engine  c. Diesel cycle  d. Rankine cycle

Last Answer : External combustion engine

Gasoline and Diesel Engines are best described by the _________.  a. Otto Cycle  b. Burnign Cycle  c. Shikki Cycle  d. Shapa R’ Elli Cycle

Description : Gasoline and Diesel Engines are best described by the _________.  a. Otto Cycle  b. Burnign Cycle  c. Shikki Cycle  d. Shapa R’ Elli Cycle

Last Answer : Otto Cycle

Which of the following engines is the most efficient?  a. Isobaric expansion  b. Adiabatic compression  c. Adiabatic expansion  d. Isothermal expansion

Description : Which of the following engines is the most efficient?  a. Isobaric expansion  b. Adiabatic compression  c. Adiabatic expansion  d. Isothermal expansion

Last Answer : Isobaric expansion

When cut-off ratio is __________ the efficiency of Diesel cycle approaches to Otto cycle efficiency.  A. zero  B. 1/5  C. 4/5  D. 1

Description : When cut-off ratio is __________ the efficiency of Diesel cycle approaches to Otto cycle efficiency.  A. zero  B. 1/5  C. 4/5  D. 1

Last Answer : Answer: A

Helium ( R= 0.4698 BTU/lbm-˚R ) is compressed isothermally from 14.7 psia and 68 ˚F. The compression ratio is 1:4. Calculate the work done by the gas.  A. –1454 BTU/lbm  B. -364 BTU/lbm  C.-187BTU/lbm  D.46.7 BTU/lbm Formula: W = RT ln (V2/V1)

Description : Helium ( R= 0.4698 BTU/lbm-˚R ) is compressed isothermally from 14.7 psia and 68 ˚F. The compression ratio is 1:4. Calculate the work done by the gas.  A. –1454 BTU/lbm  B. -364 BTU/lbm  C.-187BTU/lbm  D.46.7 BTU/lbm Formula: W = RT ln (V2/V1)

Last Answer : -364 BTU/lbm

The index of compression n tends to reach ratio of specific heats y when  (a) flow is uniform and steady  (b) process is isentropic  (c) process is isothermal  (d) process is isentropic and specific heat does not change with temperature  (e) process is isentropic and specific heat changes with temperature.

Description : The index of compression n tends to reach ratio of specific heats y when  (a) flow is uniform and steady  (b) process is isentropic  (c) process is isothermal  (d) process ... specific heat does not change with temperature  (e) process is isentropic and specific heat changes with temperature.

Last Answer : Answer : d

Twenty grams of ice at 0˚C melts to water at 0˚C. How much does the entropy of the 20g change in this process?  a. 30.5 J/K  b. 24.6 J/K  c. 21.3 J/K  d. 15.7 J/K

Description : Twenty grams of ice at 0˚C melts to water at 0˚C. How much does the entropy of the 20g change in this process?  a. 30.5 J/K  b. 24.6 J/K  c. 21.3 J/K  d. 15.7 J/K

Last Answer : 24.6 J/K

What states that thermal efficiencies of all reversible heat engines operating between the same two reservoirs are the same and that no heat engine is more efficient than a reversible one operating between the same two reservoirs?  A. Ericson principle  B. Carnot principle  C. Otto principle  D. Stirling principle

Description : What states that thermal efficiencies of all reversible heat engines operating between the same two reservoirs are the same and that no heat engine is more efficient than a reversible one operating between the ... A. Ericson principle  B. Carnot principle  C. Otto principle  D. Stirling principle

Last Answer : Carnot principle

Which is the incorrect statement about Carnot cycle?  A. It is used as the alternate standard of comparison of all heat engines.  B. All the heat engines are based on Carnot cycle.  C. It provides concept of maximising work output between the two temperature limits.  D. all of the above

Description : Which is the incorrect statement about Carnot cycle?  A. It is used as the alternate standard of comparison of all heat engines.  B. All the heat engines are based on Carnot cycle.  C. It provides concept of maximising work output between the two temperature limits.  D. all of the above

Last Answer : Answer: B

Zeroth law of thermodynamics  (a) deals with conversion of mass and energy  (b) deals with reversibility and irreversibility of process  (c) states that if two systems are both in equilibrium with a third system, they are in thermal equilibrium with each other  (d) deals with heat engines  (e) does not exist.

Description : Zeroth law of thermodynamics  (a) deals with conversion of mass and energy  (b) deals with reversibility and irreversibility of process  (c) states that if two systems are both in equilibrium with a ... in thermal equilibrium with each other  (d) deals with heat engines  (e) does not exist.

Last Answer : Answer : c

Roughly what is the total weight of air in the entire earth?  a. 1 x 10^5 tons  b. 2 x 10^6 tons  c. 6 x 10^15 tons  d. 8 x 10^10 tons

Description : Roughly what is the total weight of air in the entire earth?  a. 1 x 10^5 tons  b. 2 x 10^6 tons  c. 6 x 10^15 tons  d. 8 x 10^10 tons

Last Answer : 6 x 10^15 tons

Who coined the word energy?  a. James Joule  b. Thomas Young  c. Rudolf Diesel  d. Kelvin

Description : Who coined the word energy?  a. James Joule  b. Thomas Young  c. Rudolf Diesel  d. Kelvin

Last Answer : Thomas Young

Which of the following is least efficient?  a. Gas turbine  b. Diesel engine  c. Carnot engine  d. Gasoline engine

Description : Which of the following is least efficient?  a. Gas turbine  b. Diesel engine  c. Carnot engine  d. Gasoline engine

Last Answer : Gasoline engine

Who coined the word Entropy?  a. Rudolf Clausius  b. Kelvin  c. Gabriel Volks  d. Rudolf Diesel

Description : Who coined the word Entropy?  a. Rudolf Clausius  b. Kelvin  c. Gabriel Volks  d. Rudolf Diesel

Last Answer : Rudolf Clausius

Which of the following cycle is used in vapor cycle power plant?  a. Brayton cycle  b. Diesel cycle  c. Ericson cycle  d. Rankine cycle

Description : Which of the following cycle is used in vapor cycle power plant?  a. Brayton cycle  b. Diesel cycle  c. Ericson cycle  d. Rankine cycle

Last Answer : Rankine cycle

Fuels that may classified conveniently in solid, liquid and gaseous.  a. Unleaded fuel  b. Diesel fuel  c. Fossil fuel  d. All of the above

Description : Fuels that may classified conveniently in solid, liquid and gaseous.  a. Unleaded fuel  b. Diesel fuel  c. Fossil fuel  d. All of the above

Last Answer : Fossil fuel

The efficiency of Diesel cycle increases with  A. decrease in cut-off  B. increase in cut-off  C. constant cut-off  D. none of these

Description : The efficiency of Diesel cycle increases with  A. decrease in cut-off  B. increase in cut-off  C. constant cut-off  D. none of these

Last Answer : Answer: A

The efficiency of Diesel cycle approaches to Otto cycle efficiency when  A. cut-off is increased  B. cut-off is decreased  C. cut-off is zero  D. cut-off is constant

Description : The efficiency of Diesel cycle approaches to Otto cycle efficiency when  A. cut-off is increased  B. cut-off is decreased  C. cut-off is zero  D. cut-off is constant

Last Answer : Answer: C

A cycle consisting of one constant pressure, one constant volume and two isentropic processes is known as  A.Carnot cycle  B.Stirling cycle  C.Otto cycle  D.Diesel cycle

Description : A cycle consisting of one constant pressure, one constant volume and two isentropic processes is known as  A.Carnot cycle  B.Stirling cycle  C.Otto cycle  D.Diesel cycle

Last Answer : Answer: D

Diesel cycle consists of following four processes  (a) two isothermals and two isentropics  (b) two isentropics, and two constant volumes.  (c) two isentropics, one constant volume and one constant pressure  (d) two isentropics and two constant pressures  (e) none of the above.

Description : Diesel cycle consists of following four processes  (a) two isothermals and two isentropics  (b) two isentropics, and two constant volumes.  (c) two isentropics, one constant volume and one constant pressure  (d) two isentropics and two constant pressures  (e) none of the above.

Last Answer : Answer : c

Carnot cycle has maximum efficiency for  (a) reversible engine  (b) irreversible engine  (c) new engine  (d) petrol engine  (e) diesel engine.

Description : Carnot cycle has maximum efficiency for  (a) reversible engine  (b) irreversible engine  (c) new engine  (d) petrol engine  (e) diesel engine.

Last Answer : Answer : a

It is used for gas turbines which operates on an open cycle where both the compression and expansion processes take place in rotating machinery.  a. Dual Cycle  b. Otto Cycle  c. Carnot Cycle  d. Brayton Cycle

Description : It is used for gas turbines which operates on an open cycle where both the compression and expansion processes take place in rotating machinery.  a. Dual Cycle  b. Otto Cycle  c. Carnot Cycle  d. Brayton Cycle

Last Answer : Brayton Cycle

Executes the entire cycle in just two strokes the power stroke and the compression stroke.  a. One-stroke engine  b. Two-stroke engine  c. Four-stroke engine  d. Eight-stroke engine

Description : Executes the entire cycle in just two strokes the power stroke and the compression stroke.  a. One-stroke engine  b. Two-stroke engine  c. Four-stroke engine  d. Eight-stroke engine

Last Answer : Two-stroke engine

When the expansion of compression of gas takes place without transfer of heat to or from the gas the process is called  a. reversible  b. adiabatic  c. polytropic  d. isothermal

Description : When the expansion of compression of gas takes place without transfer of heat to or from the gas the process is called  a. reversible  b. adiabatic  c. polytropic  d. isothermal

Last Answer : adiabatic

When the expansion of compression of gas takes place without transfer of heat or from the gas the process is called;  a. Isometric process  b. Isothermal process  c. Isobaric process  d. Adiabatic process

Description : When the expansion of compression of gas takes place without transfer of heat or from the gas the process is called;  a. Isometric process  b. Isothermal process  c. Isobaric process  d. Adiabatic process

Last Answer : Adiabatic process

The compression of the gas in two or more cylinders in place of a single cylinder compressor  a. Single Staging  b. Double Staging  c. Multistaging  d. None of the above

Description : The compression of the gas in two or more cylinders in place of a single cylinder compressor  a. Single Staging  b. Double Staging  c. Multistaging  d. None of the above

Last Answer : Multistaging

Assuming compression is according to the Law PV = C, Calculate the initial volume of the gas at a pressure of 2 bars w/c will occupy a volume of 6m³ when it is compressed to a pressure of 42 Bars.  a) 130m³  b) 136m³  c) 120m³  d) 126m³ Formula: P1V1/T1 =P2V2/T2

Description : Assuming compression is according to the Law PV = C, Calculate the initial volume of the gas at a pressure of 2 bars w/c will occupy a volume of 6m³ when it is compressed to a pressure of 42 Bars.  a) 130m³  b) 136m³  c) 120m³  d) 126m³ Formula: P1V1/T1 =P2V2/T2

Last Answer : 126m³

Water vapor at 100 KPa and 150°C is compressed isothermally until half the vapor has condensed. How much work must be performed on the steam in this compression process per kilogram?  a) -1384.7 kJ  b) 1384.7 kJ  c) -2384.7 kJ  d) 2384.7 kJ

Description : Water vapor at 100 KPa and 150°C is compressed isothermally until half the vapor has condensed. How much work must be performed on the steam in this compression process per kilogram?  a) -1384.7 kJ  b) 1384.7 kJ  c) -2384.7 kJ  d) 2384.7 kJ

Last Answer : -1384.7 kJ

What is a form of mechanical work which is related with the expansion and compression of substances?  A. Boundary work  B. Thermodynamic work  C. Phase work  D. System work

Description : What is a form of mechanical work which is related with the expansion and compression of substances?  A. Boundary work  B. Thermodynamic work  C. Phase work  D. System work

Last Answer : Boundary work

During which of the following process does heat rejection takes place in Carnot cycle?  A. Isothermal expansion  B. Isentropic expansion  C. Isothermal compression  D. Isentropic compression

Description : During which of the following process does heat rejection takes place in Carnot cycle?  A. Isothermal expansion  B. Isentropic expansion  C. Isothermal compression  D. Isentropic compression

Last Answer : Answer: C

A process, in which the temperature of the working substance remains constant during its expansion or compression, is called  A. isothermal process  B. hyperbolic process  C. adiabatic process  D. polytropic process

Description : A process, in which the temperature of the working substance remains constant during its expansion or compression, is called  A. isothermal process  B. hyperbolic process  C. adiabatic process  D. polytropic process

Last Answer : Answer: A

In order that a cycle be reversible, following must be satisfied  (a) free expansion or friction resisted expansion/compression process should not be encountered  (b) when heat is being absorbed, temperature of hot source and working sub¬stance should be same  (c) when beat is being rejected, temperature of cold source and working sub-stance should be same  (d) all of the above  (e) none of the above.

Description : In order that a cycle be reversible, following must be satisfied  (a) free expansion or friction resisted expansion/compression process should not be encountered  (b) when heat is being absorbed, temperature of hot ... sub-stance should be same  (d) all of the above  (e) none of the above.

Last Answer : Answer : d

Which Has More Efficiency: Diesel Engine Or Petrol Engines?

Description : Which Has More Efficiency: Diesel Engine Or Petrol Engines?

Last Answer : Off course Diesel engine has the better efficiency out of two.

Find the change in internal energy of 5 lb. of oxygen gas when the temperature changes from 100 ˚F to 120 ˚F. CV = 0.157 BTU/lbm-˚R  A.14.7 BTU  B.15.7 BTU  C. 16.8 BTU  D. 15.9 BTU Formula: U= mcv T

Description : Find the change in internal energy of 5 lb. of oxygen gas when the temperature changes from 100 ˚F to 120 ˚F. CV = 0.157 BTU/lbm-˚R  A.14.7 BTU  B.15.7 BTU  C. 16.8 BTU  D. 15.9 BTU Formula: U= mcv T

Last Answer : 15.7 BTU

From the steam table, determine the average constant pressure specific heat (c) of steam at 10 kPa and45.8 ˚C  A.1.79 kJ/ kg-˚C  B.10.28 kJ/ kg-˚C  C.30.57 kJ/ kg-˚C  D. 100.1 kJ/ kg-˚C Formula: h = c T ∆ ∆ From the steam table At 47.7 ˚C h= 2588.1 kJ/ kg At 43.8 ˚C h= 2581.1 kJ/ kg

Description : From the steam table, determine the average constant pressure specific heat (c) of steam at 10 kPa and45.8 ˚C  A.1.79 kJ/ kg-˚C  B.10.28 kJ/ kg-˚C  C.30.57 kJ/ kg-˚C  D. 100.1 kJ/ kg-˚C Formula: h = c T ∆ ∆ From the steam table At 47.7 ˚C h= 2588.1 kJ/ kg At 43.8 ˚C h= 2581.1 kJ/ kg

Last Answer : 1.79 kJ/ kg-˚C

How many kilocalories of heat are required to heat 750 g of water from 35˚C to 55˚C.  a. 15  b. 1500  c. 1.5 x 10^4  d. 6.3 x 10^4

Description : How many kilocalories of heat are required to heat 750 g of water from 35˚C to 55˚C.  a. 15  b. 1500  c. 1.5 x 10^4  d. 6.3 x 10^4

Last Answer : 15

For the same capacity engines, the compression ratio of diesel engine a. is lower than the compression ratio of SI engine b. is higher than the compression ratio of SI engine c. is same as the compression ratio of SI engine d. cannot say

Description : For the same capacity engines, the compression ratio of diesel engine a. is lower than the compression ratio of SI engine b. is higher than the compression ratio of SI engine c. is same as the compression ratio of SI engine d. cannot say

Last Answer : ANSWER b. is higher than the compression ratio of SI engine

What is the resulting pressure when one pound of air at 15 psia and 200 ˚F is heated at constant volume to 800 ˚F?  A.15 psia  B. 28.6 psia  C. 36.4 psia.  D. 52.1 psia Formula : T1/p1 = T2/p2 p2= p1T2 / T1

Description : What is the resulting pressure when one pound of air at 15 psia and 200 ˚F is heated at constant volume to 800 ˚F?  A.15 psia  B. 28.6 psia  C. 36.4 psia.  D. 52.1 psia Formula : T1/p1 = T2/p2 p2= p1T2 / T1

Last Answer : 28.6 psia

Water is flowing through a 1 foot diameter pipe at the rate of 10ft/sec. What is the volume flow rate of water in ft³/sec?  a. 7.85  b. 6.85  c. 8.85  d. 5.85 V = Aν

Description : Water is flowing through a 1 foot diameter pipe at the rate of 10ft/sec. What is the volume flow rate of water in ft³/sec?  a. 7.85  b. 6.85  c. 8.85  d. 5.85 V = Aν

Last Answer : 7.85

One erg is equivalent to how many joules?  A. 10^-8  B. 10^-7  C. 10^-6  D. 10^-5

Description : One erg is equivalent to how many joules?  A. 10^-8  B. 10^-7  C. 10^-6  D. 10^-5

Last Answer : 10^-7

A 0.064 kg of octane vapor (MW = 114) is mixed with0.91 kg of air (MW = 29.0) in the manifold of an Engine. The total pressure in the manifold is 86.1 kPa, and a temperature is 290 K. assume octane behaves ideally. What is the partial pressure of the air in the mixture in KPa?  a. 46.8  b. 48.6  c. 84.6  d. 64.8

Description : A 0.064 kg of octane vapor (MW = 114) is mixed with0.91 kg of air (MW = 29.0) in the manifold of an Engine. The total pressure in the manifold is 86.1 kPa, and a temperature is 290 K. assume octane behaves ideally. What is ... of the air in the mixture in KPa?  a. 46.8  b. 48.6  c. 84.6  d. 64.8

Last Answer : 84.6

How many Newton’s (N) in 900,000 dynes?  a) 8 Newton’s  b) 9 Newton’s  c) 7 Newton’s  d) 6 Newton’s Formula: 1Newton (N)=100,000dynes

Description : How many Newton’s (N) in 900,000 dynes?  a) 8 Newton’s  b) 9 Newton’s  c) 7 Newton’s  d) 6 Newton’s Formula: 1Newton (N)=100,000dynes

Last Answer : 9 Newton’s

A certain gas, with cp = 0.529Btu/ lb. °Rand R = 96.2ft.lb/lb. °R, expands from 5 cu ft and 80°F to 15 cu ft while the pressure remains constant at 15.5psia. Compute for T2.  a.1520°R  b. 1620°R  c. 1720°R  d. 1820°R formula: T2= T1V2/V1

Description : A certain gas, with cp = 0.529Btu/ lb. °Rand R = 96.2ft.lb/lb. °R, expands from 5 cu ft and 80°F to 15 cu ft while the pressure remains constant at 15.5psia. Compute for T2.  a.1520°R  b. 1620°R  c. 1720°R  d. 1820°R formula: T2= T1V2/V1

Last Answer : 1620°R

A certain gas with cp = 0.529Btu/lb°R and R = 96.2ft/lbºR expands from 5 ft and 80ºF to 15 ft while the pressure remains constant at 15.5 psia.  a. T2=1.620ºR, ∫H = 122.83 Btu  b. T2 = 2°R, ∫H = 122.83 Btu  c. T2 = 2.620ºR, ∫H = 122.83 Btu  d. T2 = 1°R, ∫H = 122.83 Btu T2= V2(t2)/V1 and ∫H = mcp (T2-T1)

Description : A certain gas with cp = 0.529Btu/lb°R and R = 96.2ft/lbºR expands from 5 ft and 80ºF to 15 ft while the pressure remains constant at 15.5 psia.  a. T2=1.620ºR, ∫H = 122.83 Btu  b. T2 = 2°R, ∫H = 122.83 Btu  c. ... , ∫H = 122.83 Btu  d. T2 = 1°R, ∫H = 122.83 Btu T2= V2(t2)/V1 and ∫H = mcp (T2-T1)

Last Answer : T2=1.620ºR, ∫H = 122.83 Btu