A jet engine works on the principle of-A. Conservation of energyB. Conservation of momentumC. Conservation of massD. Conservation of temperature

In order to solve this question, we will firstly look into the concept of jet engine and its working. Then we will compare all the concepts given as options in the question to get the required answer. Complete step-by-step solution - A jet engine is a type of reaction engine discharging a fast-moving jet that generates thrust by jet propulsion. While this broad definition can include rocket, water jet, and hybrid propulsion, the term jet engine typically refers to an air breathing jet engine such as a turbojet, turbofan, ramjet or pulse jet. In general, jet engines are combustion engines. Air breathing jet engines typically feature a rotating air compressor powered by a turbine, with the leftover power providing thrust through the propelling nozzle- this process is known as the Brayton thermodynamic cycle. Jet aircraft use such engines for long-distance travel. Jet engines power jet aircraft, cruise missiles and unnamed aerial vehicles. All jet engines are reaction engines that generate thrust by emitting a jet of fluid rewards at relatively high speed. In jet engines, a large volume of gases produced by the combustion of fuel is allowed to escape through a jet in the backward direction. Due to the very high speed or velocity, the backward rushing gases have a large momentum. They impart an equal and opposite momentum to the jet engine due to which the jet engine moves forward with a great speed. Thus, we can say that the jet engine works on the principle of conservation of momentum. Therefore, option B is correct. Note- While solving this question, we must know that the term jet engine typically refers to an air breathing jet engine such as a turbojet, turbofan, ramjet or pulse jet. Also one must know that the jet engines are also known as combustion engines.