Platonic solid

Examples of Platonic solid in the following topics:

• Are Real Dice Fair?

  • The other four Platonic solids are the most common non-cubical dice; these can make for 4, 8, 12, and 20 faces .
  • A Platonic solids set of five dice; tetrahedron (four faces), cube/hexahedron (six faces), octahedron (eight faces), dodecahedron (twelve faces), and icosahedron (twenty faces).

• Astronomy

  • This region was said to only have uniform circular motion on solid spheres, which meant that it would be impossible for a comet to enter into the area.
  • The book described his model that used Pythagorean mathematics and the five Platonic solids to explain the number of planets, their proportions, and their order.
  • This work also demonstrated that the motion of objects on Earth and of celestial bodies could be described by the same principles.His laws of motion were to be the solid foundation of mechanics; his law of universal gravitation combined terrestrial and celestial mechanics into one great system that seemed to be able to describe the whole world in mathematical formulae.

• Amorphous Solids

  • Solids can be divided into two classes: crystalline and amorphous.
  • These solids are stabilized by the regular pattern of their atoms.
  • Most amorphous solids have some short-range order.
  • However, amorphous solids are common to all subsets of solids.
  • Most classes of solid can be found in an amorphous form.

• Solid to Gas Phase Transition

  • In these cases, the transition from the solid to the gaseous state requires an intermediate liquid state.
  • The reverse process of sublimation is deposition (i.e., gas to solid).
  • For example, solid iodine, I2, is easily sublimed at temperatures around 100°C.
  • There are other solids whose vapor pressure overtakes that of the liquid before melting can occur.
  • Solid carbon dioxide (known as "dry ice") sublimes into the air.

• Phases of Matter

  • There are four states of matter: solid, liquid, gas, and plasma.
  • A solid is in a state of matter that maintains a fixed volume and shape.
  • A solid's particles fit closely together .
  • A solid can change to a liquid with an enthalpy increase.
  • The process of a liquid going to a solid is known as melting.

• Molecular Crystals

  • Molecules held together by van der Waals forces form molecular solids.
  • This latter property often gives such solids a distinctive odor.
  • Whereas the characteristic melting point of metals and ionic solids is ~1000 °C, most molecular solids melt well below ~300 °C.
  • Molecular solids also have relatively low density and hardness.
  • Conductivity of molecular solids can be induced by "doping" fullerenes (e.g., C60).

• The Rise of the Vernacular

  • The 1250s saw a major change in Italian poetry as the Dolce Stil Novo (Sweet New Style, which emphasized Platonic rather than courtly love) came into its own, pioneered by poets like Guittone d'Arezzo and Guido Guinizelli.
  • Platonic ideas were revived and put to the service of Christianity.

• Alloys

  • An alloy is a mixture or metallic solid solution composed of two or more elements.
  • An alloy is a mixture or metallic-solid solution composed of two or more elements.
  • Complete solid solution alloys give single solid phase microstructure.
  • Complete solid solution alloys give single solid phase microstructure.
  • Unlike pure metals, most alloys do not have a single melting point; rather, they have a melting range in which the substance is a mixture of solid and liquid.

• Liquid to Solid Phase Transition

  • Most liquids freeze by crystallization, the formation of a crystalline solid from the uniform liquid.
  • In the presence of irregularities on the surface of the containing vessel, solid or gaseous impurities, pre-formed solid crystals, or other nucleators, heterogeneous nucleation may occur.
  • Matter exists as solids, liquids and gases, and can change state between these.
  • On the right side of the barrier is a solid material (large atoms).
  • How quickly do the more energetic atoms melt the solid?

• Three States of Matter

  • A solid's particles are packed closely together.
  • As a result, a solid has a stable, definite shape and a definite volume.
  • Solids can only change shape under force, as when broken or cut.
  • A solid can transform into a liquid through melting, and a liquid can transform into a solid through freezing.
  • It can also exist in equilibrium with a liquid (or solid), in which case the gas pressure equals the vapor pressure of the liquid (or solid).