Geocentric view and its evolution through time.

https://en.wikipedia.org/wiki/Copernican_Revolution

Epicycle: http://demonstrations.wolfram.com/OrbitsWithEpicyclesOnADeferent/

The unit of angle.  Gradient: https://en.wikipedia.org/wiki/Gradian

 

Supernova brightness

• Mutually orbiting each other,
• and velocity required for circular orbit
• Escape velocity
• Instability 4 bodies 0.001, -84, 0, 86, -150

http://phet.colorado.edu/en/simulation/legacy/my-solar-system

The strength of electrostatic force.

Conic sections: http://demonstrations.wolfram.com/PlaneCrossSectionsOfTheSurfaceOfACone/

Determinant, Cross Product, Dot Product

http://demonstrations.wolfram.com/DotProduct/

http://demonstrations.wolfram.com/CrossProductOfVectors/

Torque

http://phet.colorado.edu/en/simulation/legacy/torque

Oscillation

http://phet.colorado.edu/en/simulation/legacy/mass-spring-lab

Manipulate[
Show[
ParametricPlot3D[{Cos[t], Sin[t], 0}, {t, 0, 2 Pi},
PlotRange -> {{-1.1, 1.1}, {-1.1, 1.1}, {-1.1, 1.1}}],
Graphics3D[{Red, Sphere[{Cos[theta], Sin[theta], 0}, 0.1]}]
]
, {theta, 0, 2 Pi}, SaveDefinitions -> True]

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