Turbojet vs. Turbofan engines MCQs – Aerospace

1. What is the primary difference between a turbojet and a turbofan engine?
(A) A turbojet generates all its thrust from exhaust gases, while a turbofan uses a fan to bypass air around the engine core, increasing efficiency.
(B) A turbofan engine produces all its thrust from exhaust gases, while a turbojet engine uses a fan to bypass air.
(C) A turbojet engine is quieter and more fuel-efficient than a turbofan engine.
(D) A turbofan engine is used for high-speed supersonic flights, whereas a turbojet is used for commercial airliners.

2. How does the bypass ratio affect the performance of a turbofan engine compared to a turbojet engine?
(A) A lower bypass ratio increases the efficiency of a turbofan engine.
(B) The bypass ratio improves efficiency and makes the turbofan quieter compared to a turbojet.
(C) A higher bypass ratio reduces efficiency in a turbofan engine.
(D) A turbojet engine always has a higher bypass ratio than a turbofan engine.

3. Which engine type generally provides higher thrust for a given fuel consumption?
(A) Turbojet
(B) Turbofan
(C) Both provide the same efficiency
(D) Neither is fuel-efficient

4. In terms of noise, which engine type is generally quieter?
(A) Turbojet
(B) Turbofan
(C) Both have the same noise levels
(D) Neither is designed for noise reduction

5. What is the impact of a turbofan’s bypass ratio on its fuel efficiency compared to a turbojet?
(A) A higher bypass ratio improves fuel efficiency in a turbofan engine.
(B) A lower bypass ratio improves fuel efficiency in a turbofan engine.
(C) A turbojet engine is always more fuel-efficient than a turbofan.
(D) The bypass ratio has no effect on fuel efficiency.

6. Which engine type is more suitable for high-speed flight?
(A) Turbojet
(B) Turbofan
(C) Both are equally suitable
(D) Neither is used for high-speed flights

7. For subsonic flight, which engine type is typically more efficient?
(A) Turbojet
(B) Turbofan
(C) Both are equally efficient
(D) Neither is suitable for subsonic flight

8. How does the presence of a fan in a turbofan engine affect its thrust production?
(A) It increases thrust by accelerating more air.
(B) It reduces thrust by slowing the exhaust gases.
(C) It has no impact on thrust.
(D) It only affects fuel consumption, not thrust.

9. What is the primary advantage of using a turbofan engine in commercial airliners?
(A) Higher noise levels
(B) Lower fuel efficiency
(C) Better fuel efficiency and reduced noise
(D) Less thrust production

10. Which engine type generally has a higher specific thrust?
(A) Turbojet
(B) Turbofan
(C) Both have the same specific thrust
(D) Neither is designed for thrust production