How do jet engines create so much thrust?
In: Technology
Basically jet engines scoop up a bunch of air, heat it up so that it’s really hot, and then use that heat in the air to accelerate it to high speeds and send it out the back. This creates tons of thrust.
To go slightly more in depth, jet engines are basically momentum engines, they use combustion to convert the chemical energy in the fuel to thermal energy in the air and then into kinetic energy as the air is accelerated. Since the air then has a ton of momentum going backwards, by conservation of momentum the airplane/engine has to get equal momentum going forward, which is basically what thrust is (Newton’s 2nd Law). The equation for jet thrust is F = mdot*Veq, where mdot is the mass flow rate of the air, and Veq is the difference between the exhaust velocity and the forward velocity of the engine (there’s also a pressure term, but that can be ignored to begin with). If you are interested in more specific details about jet engines, I would suggest looking into the Brayton cycle, the different types of jet engines (turbojet, turbofan, ramjet, etc.), and some derivations of jet engine thrust equations. Here’s a NASA website with some more details on turbojet thrust:
[NASA Website](https://www.grc.nasa.gov/WWW/K-12/airplane/turbth.html)
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