Question

question 6 of 10 which of these best describes a flight that is approaching the speed of sound? a. subsonic speeds help the engines work more efficiently. b. less lift is created because there are fewer air molecules. c. there is not enough thrust to propel the airplane past the sound waves. d. more drag is created because the air molecules are not moving out of the way of the airplane.

Explanation:

When an aircraft approaches the speed of sound (transonic flight), air molecules in front of the aircraft don't have time to move out of the way, creating a shock - wave and increased drag. Subsonic speeds are below the speed of sound and not relevant here. Lift is not mainly related to the number of air molecules in this context. Thrust is not the main issue when approaching the speed of sound compared to the drag caused by air molecule behavior.

Answer:

D. More drag is created because the air molecules are not moving out of the way of the airplane.