Question

What is net propulsive force?

(a) The stream force exited at the exit of the engine

(b) The difference between the stream force entering and leaving the engine

(c) The stream force entering at the entrance of the engine

(d) The product of stream force entering and leaving the engine

This question was posed to me in an interview for internship.

My enquiry is from Thrust Producing Power Plant in portion Aircraft Force Systems and the Equations of Motion of Aircraft Performance

Answer 1

Correct option is (b) The difference between the stream force entering and leaving the engine

Easy explanation: The net propulsive force is the difference between the stream force entering and leaving the engine. It is represented by FN. The thrust produced by an aircraft is depended on the net propulsive force.