Thermodynamics Ultimate Trivia Quiz!
.
- 1.A Diesel engine has a compression ratio of 15. If the air drawn into the engine is at 300 K and 100 kPa, what will be the pressure during combustion?
- A.
4400 kPa
- B.
290 kPa
- C.
13,000 kPa
- D.
None of these answers are close (within 100 kPa).
- 2.A Diesel engine has a compression ratio of 15. If the air drawn into the engine is at 300 K and 100 kPa, what will be the temperature before combustion starts?
- A.
6050 K
- B.
880 K
- C.
1360 K
- D.
None of these answers are close (within 100 K).
- 3.In a Diesel engine, the temperature after compression is 1200 K. We then add 800 kJ/kg of energy to the flow during combustion. What is the temperature after combustion?
- A.
The temperature doesn't change during combustion in a diesel engine.
- B.
1800 K
- C.
2300 K
- D.
2000 K
- 4.In a normal combustion engine (based on an Otto cycle) the temperature after compression is 1200 K. We then add 800 kJ/kg of energy to the flow during combustion. What is the temperature after combustion?
- A.
The temperature doesn't change during combustion in an Otto cycle.
- B.
1800 K
- C.
2300 K
- D.
2000 K
- 5.What are the SI units of the Universal Gas constant R?
- A.
J / K
- B.
J / kg. K
- C.
J / mol. K
- D.
None of these options is correct.
- 6.An ideal gas with a density of 3 kg/m3 at 300 K has a pressure of 250 kPa. What is the molar mass (grams / mol) of this gas?
- A.
30 grams / mol
- B.
25 grams / mol
- C.
35 grams / mol
- D.
None of these options is close to the correct answer.
- 7.
Consider the nozzle shown here. Which of the equations below is most correct if the velocity of the flow at 2 is much higher than the velocity at 1?- A.
This equation
- B.
This equation
- C.
This equation
- D.
This equation
- 8.
Consider the flow mixer as shown, which mixes water of different temperatures. The inflow at A is 10 kg/s at 50 C. The inflow at B is 5 kg/s at 100 C, and the inflow at C is 2 kg/s at 200 C. Compute the exit temperature at D, assuming the flow is completely mixed. Choose the closest answer from the list below.
- A.
82 C
- B.
75 C
- C.
96 C
- D.
115 C
- 9.
Consider the flow mixer as shown, which mixes water of different temperatures. The inflow at A is 10 kg/s at 50 C. The inflow at B is 5 kg/s at 100 C, and the inflow at C is 2 kg/s at 200 C. Assuming the flow is completely mixed, compute the irreversibility. Choose the closest answer from those shown below.
- A.
160 kW
- B.
175 kW
- C.
190 kW
- D.
None of these answers are within 10 kW of the correct solution.
- 10.
For the Rankine cycle shown here, the boiler operates at a pressure of 3 MPa with a maximum temperature of 450 C. The temperature in the condenser is 60 C. Compute the Carnot cycle efficiency.
- A.
0.55 (55%)
- B.
0.5 (50%)
- C.
0.6 (60%)
- D.
0.45 (45%)
- 11.
For the Rankine cycle shown here, the boiler operates at a pressure of 3 MPa with a maximum temperature of 450 C. The temperature in the condenser is 60 C. Compute the thermal efficiency of this Rankine cycle.
- A.
0.54 (54%)
- B.
0.42 (42 %)
- C.
0.26 (26 %)
- D.
0.32 (32 %)
- 12.
A refrigerator using R-134a as the working fluid has a minimum temperature of -10 C and a maximum pressure of 2 MPa. Assuming an ideal refrigeration cycle as shown in this figure, compute the Coefficient of Performance (COP). (Hint: Compute QL and QH first)
- A.
1.9
- B.
2.0
- C.
1.8
- D.
0.9
- 13.The back work ratio is the ratio of the power required by the pump (WP) divided by the power created by the turbine (WT). This is much higher for a Brayton cycle than for a Rankine cycle. Select the reasons for this from the list shown below.
- A.
Liquids are easier to pump than gases are to compress.
- B.
Because steam contains more energy than air for any given temperature and pressure.
- C.
Because the specific heat capacity of water is higher than that of air.
- D.
The difference between the specific volume of the working fluid in the turbine and pump is much greater for a Rankine cycle. For a Brayton cycle, the difference is much smaller.
- 14.
Consider the T-s diagram shown for a power producing cycle. Which type of power cycle is this?
- A.
Brayton Cycle
- B.
Otto Cycle
- C.
Air Propulsion Cycle
- D.
There is not enough information to choose one option.
- 15.
Consider the standard (ideal air) jet propulsion device shown. The pressure and temperature entering the jet are 90 kPa, 290 K. The compression ratio is 14 to 1 (i.e. 14:1) and the temperature after combustion is 1500 K. Compute the velocity of the air leaving the nozzle assuming that the pressure at the nozzle exit is 90 kPa.
- A.
970 m/s
- B.
340 m/s (the speed of sound at 290 K, 90 kPa)
- C.
680 m/s
- D.
There is not enough information to solve this problem.
Questions: 56 | Attempts: 3331 | Last updated: Mar 22, 2022
-
Sample QuestionWhich of the below is not a type of heat transfer?
Questions: 62 | Attempts: 2059 | Last updated: Mar 22, 2022
-
Sample QuestionIn an isothermal process, there is no change in
Questions: 10 | Attempts: 1544 | Last updated: Mar 22, 2022
-
Sample QuestionTo save more energy you should turn the heat high in the winter.
- Acceleration Quizzes
- Acoustic Quizzes
- Chapters Of Physics Quizzes
- Distance Quizzes
- Electrolysis Quizzes
- Esd Quizzes
- Frequency Quizzes
- Lens Quizzes
- Light And Reflection Quizzes
- Logic Gate Quizzes
- Magnetic Field Quizzes
- Motion Quizzes
- Online Physics Quizzes
- Optics Quizzes
- Physics Of Sound Quizzes
- Practice Physics Quizzes
- Properties Of Matter Quizzes
- Quantum Physics Quizzes
- Reflection Quizzes
- Refraction Quizzes
- Secondary 3 Physics Quizzes
- Sound Quizzes
- Speed Of Light Quizzes
- Velocity Quizzes
- Velocity And Speed Quizzes
- Work And Energy Quizzes
Back to top