How does a Jet Engine Work?

            A jet engine works on the principle of Newton’s third law of motion, that is, every action has an equal and opposite reaction. Its working can be compared to the action of a boat in which the boatman pushes the water back with his oar, thereby getting a forward thrust which moves the boat forward.

A Jet Engine

            In simple words, according to Newton’s law, the action of pushing the water backwards produces the opposite reaction of the forward movement of the boat. Similarly, a jet engine ejects pushes backward gases to the rear at a high speed, and the resulting opposite reaction gives a forward motion to the aircraft. But how is this gas produced and how is it released with such a great force?

            Jet engines burn fuel to make hot gases. The hot gases blast out form the rear nozzle at high speed, thus pushing the engine forward at an equal speed.

            All jet engines have means of injecting fuel into the combustion chamber. There the burnt fuel produces a great amount of hot gases. It is like an explosion. These hot gases are released from the rear of the engine with great force, which pushes the engine forward. As the engines are fixed to the aircraft, the entire aircraft moves forward. This forward force is called thrust.

            The forward thrust is similar to the motion of an air-filled balloon when the air form it is released suddenly. The balloon moves in the direction, opposite to that of the nozzle from which the air escapes. The force or thrust of air is responsible for pushing the balloon in the opposite direction.

            Rockets also work on the same principle. The main difference between jets and rockets is the source of oxygen. A jet engine takes oxygen form the air through intake nozzles, but a rocket carries its own oxygen supply in the far of liquid oxygen in tank or in the form of solid fuel. Jet engines have compressors to compress the sucked in air before it is mixed with the fuel and burnt in the combustion helps to increase the force of explosion in the engine, thereby producing greater thrust.