Jet propulsion: identify the correct thrust mechanism. Choose the statement that correctly describes how thrust is produced in jet propulsion systems.
Mechanical Engineering
Compressors, Gas Dynamics and Gas Turbines
Difficulty: Easy
Choose an option
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AThe propulsive matter is ejected from within the propelled body.
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BThe propulsive matter is caused to flow around the propelled body.
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CIts functioning does not depend upon presence of air.
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Dnone of the above
Answer
Correct Answer: The propulsive matter is ejected from within the propelled body.
Explanation
Concept/ApproachJet propulsion (including turbojets and rockets) produces thrust by high-velocity ejection of propellant/exhaust gases from within the vehicle, generating a reaction force according to momentum conservation.
Option checkA Correct for jets/rockets.B Describes propellers, not jets.C Not generally true for air-breathing jets (requires air); it is true only for rockets.
Final AnswerThe propulsive matter is ejected from within the propelled body.