Sir Isaac Newton first presented his three laws
of motion in the "Principia Mathematica Philosophiae Naturalis"
in 1686. His third law states that for every action (force) in nature
there is an equal and opposite reaction. In other words, if object A
exerts a force on object B, then object B also exerts an equal and
opposite force on object A. Notice that the forces are exerted on
In aerospace engineering, the principal of action and reaction is very
important. Newton's third law explains the generation of
by a rocket engine. In a rocket engine, hot exhaust gas
is produced through the
of a fuel with an oxidizer.
The hot exhaust gas flows through the rocket
and is accelerated to the rear of the rocket. In re-action, a thrusting force
is produced on the engine mount.
The thrust accelerates the rocket as described by Newton's
Newton's Laws of Motion:
Rocket Propulsion Activity: Grade 9-10
Fundamental Terminology: Grade 10-12
Hero Engine: Grade 6-10
Rocket Car: Grade 6-10
Rocket Pinwheel: Grade 6-10
Newton Car: Grade 10-12
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