Introduction to circular motion

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CIRCULAR MOTION
The Magic of

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After Aristotle
Aristotle’s concepts may be
wrong in the modern eyes. But
it seems to us that there is a few
strokes of truth in the
fundamentals underlying the
concepts.
Let us check it in more details.

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Circular Motion
Circular motion, as its name suggests, is motion in a circle. An electrons flying around a
nucleus, a merry go round, a compact disc, a Ferris wheel, the moon orbiting the earth,
etc. are events belonging to such a kind of motion.

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Curvilinear & Circular Motion
Circular motion is a special case of plane curvilinear motion. While curvilinear
motion may involve a lot of variations in the curvatures of the motion path,
circular motion is constrained by a constant radius. Thus the curvature in
circular motion is much simpler, and as its name implies, the motion path is a
simple circle.
Curvilinear Motion Circular Motion
Centre

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Only Circular Motion
is Considered
However, curvilinear motions are in
general macro phenomena. In the micro
particle world, natural motions are
generally either rectilinear or more or
less circular, so in the coming section,
only circular and rotational motions are
considered.
This is an appropriate move, because
circular and rotational motions are the
simpler versions of curvilinear motion. It
is a more natural approach by having an
understanding of the simpler items first
and then proceed to grasp the more
complicated ones later.

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Importance of Circular Motion
Though much simpler than the free curve, circular motion plays an important
role in classical mechanics, quantum mechanics, particle physics and
astrophysics. We shall see that its popularity is in fact due to one of its natural
characteristics as significant as those of rectilinear motion.

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COPERNICUS’ & KEPLER’S ORBITALS
To be continued in: