Download Newton`s Laws of Motion

Newton’s Laws of Motion
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When a rocket lifts off it is because thrust
exceeds the weight that keeps it in place.
This reflects Newton's First Law of Motion,
which states that an object at rest will stay at
rest as long as no unbalanced force is applied.
When a rocket reaches space, atmospheric drag
(friction) is greatly reduced or eliminated.
No additional rocket thrust will be needed. Its
inertia will cause it to continue to travel
outward.
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Two forces act on a rocket being launched.
One is weight, the force generated by the
gravitational attraction of Earth on the rocket.
The other is thrust, the force that moves the
rocket.
Newton's Second Law of Motion applies here,
as force (thrust) = mass × acceleration.
This formula can also be used to determine the
rate at which a rocket accelerates, because
acceleration = force/mass.
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The movement of the high-speed exhaust in
one direction propels the rocket in the opposite
direction.
This is Newton's Third Law of Motion in
action; for every action there is an equal and
opposite reaction.
Drag is the rocket's resistance to motion caused by the
rocket's movement through air.
The nose cones of rockets are streamlined to help
reduce drag.
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Rockets must be stable in flight — they must be
able to fly in a smooth, predictable direction.
Fins help stabilize the rocket when air is
present.
They are lightweight extensions attached to the
exterior of the model rocket.
They streamline the flow of air and provide a
large surface area and help to keep the center
of pressure behind the center of mass of the
rocket.