Jet propulsion basics: A simple turbojet is essentially a gas turbine engine fitted with an inlet diffuser and a propulsive (exhaust) nozzle to produce thrust.

Introduction / Context:
A simple turbojet is the foundational air-breathing jet engine architecture used to generate propulsive thrust from a continuous gas turbine cycle.

Given Data / Assumptions:

• Core components: inlet diffuser, compressor, combustor, turbine, and exhaust nozzle.
• “Simple” indicates no afterburner, no bypass (unlike turbofans), and no mechanical power takeoff (unlike turboshafts).

Concept / Approach:
The gas turbine core raises the total temperature and pressure of air. The inlet diffuser slows and pressurizes the incoming air (static pressure rise), the compressor further raises pressure, the combustor adds heat at near-constant pressure, the turbine extracts work to drive the compressor, and the exhaust nozzle expands the hot gas to high velocity, creating thrust.

Step-by-Step Solution:

Verification / Alternative check:
Cutaway schematics of classic turbojets (e.g., early military engines) show precisely this layout without bypass streams or afterburners.

Why Other Options Are Wrong:

• Disagree: Contradicts the standard definition.
• Agree, but only with afterburning: Afterburners are optional add-ons and not required for a “simple” turbojet.
• Disagree, because a turbojet has no turbine: False; the turbine is essential to drive the compressor.

Common Pitfalls:
Confusing turbojets with turbofans (which have a fan and bypass) or turboshafts (which deliver shaft power instead of pure jet thrust).

Final Answer:
Agree