Question

During a rocket launch from Sea Level to Space, a fixed-geometry nozzle that is over-expanded at the launch pad will eventually become

• A. More over-expanded as it gains altitude
• B. Perfectly expanded, then under-expanded as back pressure drops
• C. Subsonic at the throat
• D. Extremely separated at high altitudes

Hint:

As altitude increases, \[ P_b\downarrow \] Hence, \[ \boxed{ \text{Over-expanded} \rightarrow \text{Perfectly Expanded} \rightarrow \text{Under-expanded}. } \]

Answer 1

The Correct Option is B