==Mechanical efficiency== From momentum considerations, propulsion requires material to be pushed backwards to push the vehicle forwards. In general, energy efficiency is highest when the air or exhaust gas used to propel the vehicle end up travelling as slow as possible for the required thrust, in the frame of reference of the Earth. ===Jet engin...
Found on
http://en.wikipedia.org/wiki/Propulsive_efficiency
(from the article `jet engine`) ...There is generally a great deal of energy left in the high-temperature, high-velocity jet stream exiting from the propulsor that is not fully ...
Found on
http://www.britannica.com/eb/a-z/p/122
No exact match found.
