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
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
Description : Carnot cycle efficiency depends upon (a) properties of the medium/substance used (b) condition of engine (c) working condition (d) temperature range of operation (e) effectiveness of insulating material around the engine.
Last Answer : Answer : d
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
Description : The dual combustion cycle consists of one constant pressure, two constant volume and two isentropic processes. A. Agree B. Disagree
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
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
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
Description : The efficiency of Diesei cycle with decrease in cut off (a) increases (b) decreases (c) remains unaffected (d) first increases and then decreases (e) first decreases and then increases.
Description : What is defined as the ratio of the net electrical power output to the rate of fuel energy input? A. Combustion efficiency B. Thermal efficiency C. Overall efficiency D. Furnace efficiency
Last Answer : Overall efficiency
Description : What is the ratio of the useful heat extracted to heating value? A. Combustion efficiency B. Phase efficiency C. Heat efficiency D. Work efficiency
Last Answer : Combustion efficiency
Description : If both Stirling and Carnot cycles operate within the same temperature limits, then efficiency of Stirling cycle as compared to Carnot cycle (a) more (b) less (c) equal (d) depends on other factors (e) none of the above.
Last Answer : Answer : c
Description : Heat engine deriving its power from the energy liberated by the explosion of a mixture of some hydrocarbon, in a gaseous or vaporized form. a. Dual Combustion Engine b. Internal Combustion Engine c. External Combustion Engine d. None of the above
Last Answer : Internal Combustion Engine
Description : Extensive property of a system is one whose value (a) depends on the mass of the system like volume (b) does not depend on the mass of the system, like temperature, pressure, etc. (c) is not ... the state (d) is dependent on the path followed and not on the state (e) is always constant.
Description : Intensive property of a system is one whose value (a) depends on the mass of the system, like volume (b) does not depend on the mass of the system, like temperature, pressure, etc. (c) is not ... on the state (d) is dependent on the path followed and not on the state (e) remains constant.
Last Answer : Answer : b
Description : The efficiency and work ratio of a simple gas turbine cycle are A.low B.very low C.high D.very high
Last Answer : Answer: B
Description : The ideal efficiency of a Brayton cycle with regeneration, with increase in pressure ratio will (a) increase (b) decrease (c) remain unchanged (d) increase/decrease depending on ap-plication (e) unpredictable. “
Description : Compressed air coming out from a punctured football (a) becomes hotter (b) becomes cooler1 (c) remains at the same temperature (d) may become hotter or cooler depend-ing upon the humidity of the surround¬ing air (e) attains atmospheric temperature.
Last Answer : (b) becomes cooler1
Description : The efficiency of Stirling cycle is __________ Carnot cycle. A. greater than B. less than C. equal to
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
Description : Reversed joule cycle is called (a) Carnot cycle (b) Rankine cycle (c) Brayton cycle (d) Bell Coleman cycle (e) Dual 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
Description : The efficiency of a Carnot engine depends on (a) working substance (b) design of engine (c) size of engine (d) type of fuel fired (e) temperatures of source and sink.
Last Answer : Answer : e
Description : The efficiency of Joule cycle is A. greater than Carnot cycle B. less than Carnot cycle C. equal to Carnot cycle D. none of these
Description : The efficiency of Carnot cycle is maximum for (a) gas engine (b) well lubricated engine (c) petrol engine (d) steam engine (e) reversible engine.
Description : An actual engine is to be designed having same efficiency as the Carnot cycle. Such a proposition is (a) feasible (b) impossible (c) possible (d) possible, but with lot of sophistications (e) desirable.
Description : Carnot cycle efficiency is maximum when (a) initial temperature is 0°K (b) final temperature is 0°K (c) difference between initial and final temperature is 0°K (d) final temperature is 0°C (e) initial temperature is minimum possible.
Description : Carnot cycle has maximum efficiency for (a) reversible engine (b) irreversible engine (c) new engine (d) petrol engine (e) diesel engine.
Description : A _________ is a quantity whose value depends on the path followed during a particular change in state. a. path function b. point function c. process d. cycle
Last Answer : path function
Description : Which one is the correct relation between energy efficiency ratio (EER) and coefficient of performance (COP)? A. EER = 2.34 COP B. EER = 3.24 COP C. EER = 3.42 COP D. EER = 4.23 COP
Last Answer : EER = 3.42 COP
Description : Thermal efficiency is the ratio of: A. Network input to total heat input B. Network output to total heat output C. Network output to total heat input D. Network input to total heat output
Last Answer : Network output to total heat input
Description : The ideal efficiency of a Brayton cycle without regeneration with increase ni pressure ratio will (a) increase (b) decrease (c) remain unchanged (d) increase/decrease depending on application (e) unpredictable.
Description : What refers to the minimum temperature at which combustion can be sustained? A. Burn temperature B. Kindle temperature C. Spark temperature D. Ignition temperature
Last Answer : Ignition temperature
Description : Producer gas is obtained by A. partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast B. carbonisation of bituminous coal C. passing steam over incandescent coke D. passing air and a large amount of steam over waste coal at about 650°C
Description : The gas constant (R) is equal to the __________ of two specific heats. A. sum B. difference C. product D. ratio
Description : A simple steam engine receives steam from the boiler at 180˚C and exhausts directly into the air at 100˚C. What is the upper limit of its efficiency? a. 11.28 % b. 36.77 % c. 20.36 % d. 17.66 %
Last Answer : 17.66 %
Description : For heat engine operating between two temperatures (T1>T2), what is the maximum efficiency attainable? A. Eff = 1 – (T2/T1) B. Eff = 1 - (T1/T2) C. Eff = T1 - T2 D. Eff = 1 - (T2/T1)^2
Last Answer : Eff = 1 – (T2/T1)
Description : What is the highest efficiency of heat engine operating between the two thermal energy reservoirs at temperature limits? A. Ericson efficiency B. Otto efficiency C. Carnot efficiency D. Stirling efficiency
Last Answer : Carnot efficiency
Description : What refers to the amount of heat removed from the cooled space in BTS’s for 1 watt-hour of electricity consumed? A. Cost efficiency rating B. Energy efficiency rating C. Coefficient of performance D. Cost of performance
Last Answer : Energy efficiency rating
Description : Liquid fuels have lower efficiency than solid fuels. A. True B. False
Description : Which of the following cycles has maximum efficiency (a) Rankine (b) Stirling (c) Carnot (d) Brayton (e) Joule.
Description : Which of the following represents the perpetual motion of the first kind (a) engine with 100% thermal efficiency (b) a fully reversible engine (c) transfer of heat energy from low ... its own energy (e) production of energy by temperature differential in sea water at different levels.
Description : The more effective way of increasing efficiency of Carnot engine is to (a) increase higher temperature (b) decrease higher temperature (c) increase lower temperature (d) decrease lower temperature (e) keep lower temperature constant.
Description : Vapor pressure depends only on _________. a. pressure b. force c. volume d. temperature
Last Answer : temperature
Description : Entropy change depends on (a) heat transfer (b) mass transfer (c) change of temperature (d) thermodynamic state (e) change of pressure and volume.
Description : Work done in an adiabatic process between a given pair of end states depends on (a) the end states only (b) particular adiabatic process (c) the value of index n (d) the value of heattransferred (e) mass of the system.
Description : The thermal efficiency of a diesel cycle having fixed compression ratio with increase in cut-off ratio will a. increase b. decrease c. independent d. increase or decrease depending upon other factors
Last Answer : ANSWER b. decrease
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
Description : Which of the following values characterize the state of the system? a. cycle b. process c. property d. enthalpy
Last Answer : enthalpy