The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be (A) More (B) Less (C) Same (D) Data insufficient to predict

The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be
(A) More
(B) Less
(C) Same
(D) Data insufficient to predict
by

1 Answer

Answer :

(A) More
by

Related questions

Pick out the correct statement. (A) Compression ratio of an Otto engine is comparatively higher than a diesel engine (B) Efficiency of an Otto engine is higher than that of a diesel engine for the same compression ratio (C) Otto engine efficiency decreases with the rise in compression ratio, due to decrease in work produced per quantity of heat (D) Diesel engine normally operates at lower compression ratio than an Otto engine for an equal output of work

Description : Pick out the correct statement. (A) Compression ratio of an Otto engine is comparatively higher than a diesel engine (B) Efficiency of an Otto engine is higher than that of a diesel ... Diesel engine normally operates at lower compression ratio than an Otto engine for an equal output of work

Last Answer : (B) Efficiency of an Otto engine is higher than that of a diesel engine for the same compression ratio

For same compression ratio a. Diesel cycle has lower efficiency than Otto cycle b. Diesel cycle has higher efficiency than Otto cycle c. Diesel cycle and Otto cycle have equal efficiencies d. Depends upon the load on engine

Description : For same compression ratio a. Diesel cycle has lower efficiency than Otto cycle b. Diesel cycle has higher efficiency than Otto cycle c. Diesel cycle and Otto cycle have equal efficiencies d. Depends upon the load on engine

Last Answer : Answer a. Diesel cycle has lower efficiency than Otto cycle

A diesel engine is usually more efficient than a spark ignition engine because a. Diesel being a heavier hydrocarbon, release more heat per kg than gasoline b. The air standard efficiency of diesel cycle is higher than the Otto cycle, at a fixed compression ratio c. The compression ratio of a diesel engine is higher than that of an Spark ignition engine d.Self ignition temperature of diesel is higher than that of gasoline.

Description : A diesel engine is usually more efficient than a spark ignition engine because a. Diesel being a heavier hydrocarbon, release more heat per kg than gasoline b. The air standard efficiency of diesel ... an Spark ignition engine d.Self ignition temperature of diesel is higher than that of gasoline.

Last Answer : ANSWER c. The compression ratio of a diesel engine is higher than that of an S.I engine

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

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

With increase in compression ratio, the efficiency of the otto engine (A) Increases (B) Decreases (C) Remain constant (D) Increases linearly

Description : With increase in compression ratio, the efficiency of the otto engine (A) Increases (B) Decreases (C) Remain constant (D) Increases linearly

Last Answer : (A) Increases

In diesel engine, the compression ratio as compared with the expansion ratio is a. same b. less c. more d. variable

Description : In diesel engine, the compression ratio as compared with the expansion ratio is a. same b. less c. more d. variable

Last Answer : ANSWER c. more

If the compression ratio of an engine working on Otto cycle is increased from 5 to 7 the percentage increase in efficiency will be a. 2% b. 4% c. 8% d. 14%

Description : If the compression ratio of an engine working on Otto cycle is increased from 5 to 7 the percentage increase in efficiency will be a. 2% b. 4% c. 8% d. 14%

Last Answer : ANSWER d. 14%

Air standard Otto cycle is more efficient than the diesel cycle for the same (A) Heat addition & compression ratio (B) Heat addition & pressure (C) Compression ratio & pressure (D) Cylinder dimension & rpm

Description : Air standard Otto cycle is more efficient than the diesel cycle for the same (A) Heat addition & compression ratio (B) Heat addition & pressure (C) Compression ratio & pressure (D) Cylinder dimension & rpm

Last Answer : (A) Heat addition & compression ratio

For same compression ratio and heat input a. Otto cycle is more efficient b. Diesel cycle is more efficient c. Both are equally efficient d. None of the above

Description : For same compression ratio and heat input a. Otto cycle is more efficient b. Diesel cycle is more efficient c. Both are equally efficient d. None of the above

Last Answer : ANSWER a. Otto cycle is more efficient

The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is (A) Less pronounced (B) More pronounced (C) Equal (D) Data insufficient, can't be predicted

Description : The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is (A) Less pronounced (B) More pronounced (C) Equal (D) Data insufficient, can't be predicted

Last Answer : (B) More pronounced

Which of the following has the least thermal efficiency? (A) Steam engine (B) Carnot engine (C) Diesel engine (D) Otto engine

Description : Which of the following has the least thermal efficiency? (A) Steam engine (B) Carnot engine (C) Diesel engine (D) Otto engine

Last Answer : A) Steam engine

Most high speed compression ignition engine operate on A. dual cycle B. otto cycle C. diesel cycle D.Carnot cycle

Description : Most high speed compression ignition engine operate on A. dual cycle B. otto cycle C. diesel cycle D.Carnot cycle

Last Answer : ANSWER : A

Which of the following cycle is used for Compression Ignition engine? a. Otto cycle b. Diesel cycle c. Dual cycle d. Carnot cycle

Description : Which of the following cycle is used for Compression Ignition engine? a. Otto cycle b. Diesel cycle c. Dual cycle d. Carnot cycle

Last Answer : Answer b. Diesel cycle

A pitched-blade turbine draws __________ a straight blade turbine. (A) Less power than (B) More power than (C) Same power as (D) Data insufficient to predict

Description : A pitched-blade turbine draws __________ a straight blade turbine. (A) Less power than (B) More power than (C) Same power as (D) Data insufficient to predict

Last Answer : (A) Less power than

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

An ideal air standard Otto cycle has a compression ratio of 8.5. If the ratio of the specific heats is 1.4, then what is thermal efficiency (in percentage) of the Otto cycle? a. 57.5% b. 45.7% c. 52.5% d. 95%

Description : An ideal air standard Otto cycle has a compression ratio of 8.5. If the ratio of the specific heats is 1.4, then what is thermal efficiency (in percentage) of the Otto cycle? a. 57.5% b. 45.7% c. 52.5% d. 95%

Last Answer : ANSWER a. 57.5%

What is the relation between compression ratio (rk) and the efficiency of the Otto cycle? a. efficiency decreases with increase in compression ratio b. efficiency increases with increase in compression ratio c. efficiency is not affected by change in compression ratio d. none of the above

Description : What is the relation between compression ratio (rk) and the efficiency of the Otto cycle? a. efficiency decreases with increase in compression ratio b. efficiency increases with increase in compression ratio c. efficiency is not affected by change in compression ratio d. none of the above

Last Answer : ANSWER b. efficiency increases with increase in compression ratio

The efficiency of the Otto cycle is independent of a. Heat supplied b. Compression ratio c. Ratio of specific heats d. None of the above

Description : The efficiency of the Otto cycle is independent of a. Heat supplied b. Compression ratio c. Ratio of specific heats d. None of the above

Last Answer : Answer a. Heat supplied

In otto cycle compression ratio is 8. Calculate air standard efficiency. Will it be grater than Carnot Cycle ? Justify your answer.

Description : In otto cycle compression ratio is 8. Calculate air standard efficiency. Will it be grater than Carnot Cycle ? Justify your answer. 

Last Answer : No, the Otto cycle efficiency 56.47% will always be lower than Carnot cycle efficiency. Justification: Carnot theorem states that keeping operating conditions same, Carnot engine is more efficient than any other engine. So, Otto cycle efficiency is lower than Carnot cycle efficiency. 

If the performance of diesel engine of different sizes, cylinder dimensions and power rating are to be compared, which of the following parameters can be used for such comparison? (a) Swept volume (b) Air fuel ratio (c) Specific brake fuel consumption (d) Volumetric efficiency

Description : If the performance of diesel engine of different sizes, cylinder dimensions and power rating are to be compared, which of the following parameters can be used for such comparison? (a) Swept volume (b) Air fuel ratio (c) Specific brake fuel consumption (d) Volumetric efficiency

Last Answer : Ans :c

Reynolds number for water flow through a tube of I.D. 5 cm is 1500. If a liquid of 5 centipoise viscosity and 0.8 specific gravity flows in the same pipe at the same velocity, then the pressure drop will (A) Increase (B) Decrease (C) Remain same (D) Data insufficient to predict pressure drop

Description : Reynolds number for water flow through a tube of I.D. 5 cm is 1500. If a liquid of 5 centipoise viscosity and 0.8 specific gravity flows in the same pipe at the same velocity, then the pressure drop will (A) Increase (B) Decrease (C) Remain same (D) Data insufficient to predict pressure drop

Last Answer : (A) Increase

A centrifugal pump used to pump water is used to pump an oil withspecific gravity of 0.8 at the same rate. The power consumption will now (A) Increase (B) Decrease (C) Remain same (D) Data insufficient to predict

Description : A centrifugal pump used to pump water is used to pump an oil withspecific gravity of 0.8 at the same rate. The power consumption will now (A) Increase (B) Decrease (C) Remain same (D) Data insufficient to predict

Last Answer : (B) Decrease

Two fluids are flowing through two similar pipes of the same diameter. The Reynold's number is same. For the same flow rate if the viscosity of a fluid is reduced to half the value of the first fluid, the pressure drop will (A) Increase (B) Decrease (C) Remain unchanged (D) Data insufficient to predict relative pressure drop

Description : Two fluids are flowing through two similar pipes of the same diameter. The Reynold's number is same. For the same flow rate if the viscosity of a fluid is reduced to half the value of the ... (A) Increase (B) Decrease (C) Remain unchanged (D) Data insufficient to predict relative pressure drop

Last Answer : (B) Decrease

Compare the efficiency of Otto cycle and diesel cycle for same maximum pressure with neat sketch.

Description : Compare the efficiency of Otto cycle and diesel cycle for same maximum pressure with neat sketch.

Last Answer : Comparison of efficiency of Otto Cycle and Diesel cycle for same pressure ration and same conditions The air-standard Otto and Diesel cycles are drawn on common p-v and T-s diagrams for the same pressure ... for the same pressure ratio Qs(diesel) > Qs(otto) Thus , diesel > otto 

For an engine operating on air standard Otto cycle, the clearance volume is 10% of the swept volume. The specific heat ratio of air is 1.4. The air standard cycle efficiency is a. 38.3 % b. 39.8 % c. 60.2 % d. 61.7 %

Description : For an engine operating on air standard Otto cycle, the clearance volume is 10% of the swept volume. The specific heat ratio of air is 1.4. The air standard cycle efficiency is a. 38.3 % b. 39.8 % c. 60.2 % d. 61.7 %

Last Answer : ANSWER d. 61.7%

A fuel containing carbon and carbon monoxide (but containing no hydrogen or its compounds) is burnt in pure oxygen at constant pressure. Its gross calorific value as compared to net calorific value will be (A) More (B) Less (C) Same (D) Data insufficient; can't be predicted

Description : A fuel containing carbon and carbon monoxide (but containing no hydrogen or its compounds) is burnt in pure oxygen at constant pressure. Its gross calorific value as compared to net calorific value will be (A) More (B) Less (C) Same (D) Data insufficient; can't be predicted

Last Answer : (C) Same

Most high-speed compression engines operate on a. diesel cycle b. Otto cycle c. dual cycle d. Carnot cycle

Description : Most high-speed compression engines operate on a. diesel cycle b. Otto cycle c. dual cycle d. Carnot cycle

Last Answer : ANSWER c. dual cycle

If the discharge of a centrifugal pump is throttled, then its suction lift (A) Increases (B) Decreases (C) Remains unchanged (D) Data insufficient to predict

Description : If the discharge of a centrifugal pump is throttled, then its suction lift (A) Increases (B) Decreases (C) Remains unchanged (D) Data insufficient to predict

Last Answer : (A) Increases

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

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

Which of the following cycle is used for Spark Ignition engine? a. Otto cycle b. Diesel cycle c. Dual cycle d. Carnot cycle

Description : Which of the following cycle is used for Spark Ignition engine? a. Otto cycle b. Diesel cycle c. Dual cycle d. Carnot cycle

Last Answer : Answer a. Otto cycle

The 'four stroke petrol engine' is based on – (1) Carnot-cycle (2) Otto-cycle (3) Diesel-cycle (4) Boyle's-cycle

Description : The 'four stroke petrol engine' is based on – (1) Carnot-cycle (2) Otto-cycle (3) Diesel-cycle (4) Boyle's-cycle

Last Answer : (2) Otto-cycle Explanation: A four-stroke engine (also known as four-cycle) is an internal combustion n engine in which the piston completes four separate strokes—intake, compression, power, and exhaust—during two separate revolutions of the engine's crankshaft, and one single thermodynamic cycle.

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

The ‘four stroke petrol engine’ is based on (1) Carnot-cycle (2) Otto-cycle (3) Diesel-cycle (4) Boyle’s-cycle

Description : The ‘four stroke petrol engine’ is based on (1) Carnot-cycle (2) Otto-cycle (3) Diesel-cycle (4) Boyle’s-cycle

Last Answer : Otto-cycle

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

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

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

The specific fuel consumption of a petrol engine compared to diesel engine of same H.P is A. same B.more C. less D. unpredictable

Description : The specific fuel consumption of a petrol engine compared to diesel engine of same H.P is A. same B.more C. less D. unpredictable

Last Answer : ANSWER : B

Both stearic acid and linoleic acid have 18 carbons. Linoleic acid is unsaturated, while stearic acid is saturated. The melting point of stearic acid : (a) is higher than linoleic acid (b) is lower than linoleic acid (c) is same as linoleic acid (d) can not predict, insufficient information

Description : Both stearic acid and linoleic acid have 18 carbons. Linoleic acid is unsaturated, while stearic acid is saturated. The melting point of stearic acid : (a) is higher than linoleic acid (b) is lower than linoleic acid (c) is same as linoleic acid (d) can not predict, insufficient information

Last Answer : is higher than linoleic acid

The tendency of a diesel engine to knock increases if a. engine speed is increased b. engine power is increased c. cetane number of the fuel is increased d. compression ratio is increased

Description : The tendency of a diesel engine to knock increases if a. engine speed is increased b. engine power is increased c. cetane number of the fuel is increased d. compression ratio is increased

Last Answer : ANSWER d. compression ratio is increased

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

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

In vapour compression refrigeration system, if the evaporator temperature and the condenser temperatures are -13°C and 37°C respectively, the Carnot COP will be (A) 5.2 (B) 6.2 (C) 0.168 (D) Data insufficient, can't be found out

Description : In vapour compression refrigeration system, if the evaporator temperature and the condenser temperatures are -13°C and 37°C respectively, the Carnot COP will be (A) 5.2 (B) 6.2 (C) 0.168 (D) Data insufficient, can't be found out

Last Answer : A) 5.2

What is the formula for compression (rk) ratio of the Otto cycle? a. rk = Volume of cylinder at the beginning of compression / Volume of cylinder at the end of compression b. rk = Volume of cylinder at the end of compression / Volume of cylinder at the beginning of compression c. rk = Volume of cylinder at the end of compression / clearance volume d. none of the above

Description : What is the formula for compression (rk) ratio of the Otto cycle? a. rk = Volume of cylinder at the beginning of compression / Volume of cylinder at the end of compression b. rk = Volume of cylinder ... c. rk = Volume of cylinder at the end of compression / clearance volume d. none of the above

Last Answer : ANSWER a. rk = Volume of cylinder at the beginning of compression / Volume of cylinder at the end of compression

A diesel engine compared to petrol engine, running at full load is A. less efficient B. equally efficient C. more efficient D. other factors will decide it

Description : A diesel engine compared to petrol engine, running at full load is A. less efficient B. equally efficient C. more efficient D. other factors will decide it

Last Answer : ANSWER : C

iesel engine has less reserve torque then spark ignition because ∙ Torque-speed curve is governed by volumetric efficiency of fuel pump and engine cylinder ∙ Torque is a function of thermal efficiency ∙ Diesel engine has generally low speed engine ∙ None of the above

Description : iesel engine has less reserve torque then spark ignition because ∙ Torque-speed curve is governed by volumetric efficiency of fuel pump and engine cylinder ∙ Torque is a function of thermal efficiency ∙ Diesel engine has generally low speed engine ∙ None of the above

Last Answer : ∙ Torque is a function of thermal efficiency

For the same peak pressure and heat input a. Otto cycle is more efficient b. Diesel cycle is more efficient c. Both are equally efficient d. None of the above

Description : For the same peak pressure and heat input a. Otto cycle is more efficient b. Diesel cycle is more efficient c. Both are equally efficient d. None of the above

Last Answer : ANSWER b. Diesel cycle is more efficient

Spark plug is provided in a/an (A) Engine having carburettor (B) Diesel engine (C) Compression ignition engine (D) Both (B) & (C)

Description : Spark plug is provided in a/an (A) Engine having carburettor (B) Diesel engine (C) Compression ignition engine (D) Both (B) & (C)

Last Answer : (A) Engine having carburettor

For the same maximum pressure and temperature, what is the relation among the efficiencies of the Otto cycle, the Diesel cycle and the Dual cycle? a. ηDual >ηDiesel >ηOtto b. ηDiesel >ηDual >ηOtto c. ηDiesel >ηOtto >ηDual d. ηOtto >ηDiesel >ηDual

Description : For the same maximum pressure and temperature, what is the relation among the efficiencies of the Otto cycle, the Diesel cycle and the Dual cycle? a. ηDual >ηDiesel >ηOtto b. ηDiesel >ηDual >ηOtto c. ηDiesel >ηOtto >ηDual d. ηOtto >ηDiesel >ηDual

Last Answer : ANSWER b. ηDiesel >ηDual >ηOtto

Multistage compression of air as compared to single stage compression offers the advantage of (A) Power saving per unit weight of air delivered (B) Moisture elimination in the inter-stage cooler (C) Increased volumetric efficiency (D) All (A), (B) & (C)

Description : Multistage compression of air as compared to single stage compression offers the advantage of (A) Power saving per unit weight of air delivered (B) Moisture elimination in the inter-stage cooler (C) Increased volumetric efficiency (D) All (A), (B) & (C)

Last Answer : (D) All (A), (B) & (C)

Power loss in an orificemeter is __________ that in a Venturimeter. (A) Less than (B) Same as (C) More than (D) Data insufficient, cannot be predicted

Description : Power loss in an orificemeter is __________ that in a Venturimeter. (A) Less than (B) Same as (C) More than (D) Data insufficient, cannot be predicted

Last Answer : (C) More than