Deltahedron

Foldable Polyhedron 2

Delta-Star is a polyhedral object which I invented in 1996. The type of Delta-Star corresponds to Deltahedrons. It expands and shrinks.

From playlist Handmade geometric toys

Foldable Polyhedron 1

Delta-Star is a polyhedral object which I invented in 1996. The type of Delta-Star corresponds to Deltahedrons. It expands and shrinks. Especially highly symmetric tetrahedron,octahedron,icosahedron types and hexahedron,decahedron types can transform smoothly.

From playlist Handmade geometric toys

How to Construct a Dodecahedron

How the greeks constructed the Dodecahedron. Euclids Elements Book 13, Proposition 17. In geometry, a dodecahedron is any polyhedron with twelve flat faces. The most familiar dodecahedron is the regular dodecahedron with regular pentagons as faces, which is a Platonic solid. A regular dode

From playlist Platonic Solids

What is a concave polygon

👉 Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

Periodic Table Part 4: Boron Group (B, Al, Ga, In, Tl, Nh)

It's time to check out Group 13 on the periodic table, the boron group. This includes boron, aluminum, gallium, indium, thallium, and nihonium. What can we say about their properties, reactivities, and applications? Let's find out! Watch the whole Inorganic/Organometallic Chemistry playli

From playlist Inorganic/Organometallic Chemistry

How to find the volume or a triangular prism

👉 Learn how to find the volume and the surface area of a prism. A prism is a 3-dimensional object having congruent polygons as its bases and the bases are joined by a set of parallelograms. A prism derives its name from the shape of its base, i.e. a prism with triangles as its bases are ca

From playlist Volume and Surface Area

What is the difference between convex and concave

👉 Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

What is a triangular prism and how do we find the surface area

👉 Learn how to find the volume and the surface area of a prism. A prism is a 3-dimensional object having congruent polygons as its bases and the bases are joined by a set of parallelograms. A prism derives its name from the shape of its base, i.e. a prism with triangles as its bases are ca

From playlist Volume and Surface Area

Sketch a net from a 3D figure

👉 Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

How to find the volume of a pentagonal pyramid

👉 Learn how to find the volume and the surface area of a pyramid. A pyramid is a 3-dimensional object having a polygon as its base and triangular surfaces converging at a single point called its apex. A pyramid derives its name from the shape of its base, i.e. a pyramid with a triangular b

From playlist Volume and Surface Area

What is a rectangular prism

👉 Learn how to find the volume and the surface area of a prism. A prism is a 3-dimensional object having congruent polygons as its bases and the bases are joined by a set of parallelograms. A prism derives its name from the shape of its base, i.e. a prism with triangles as its bases are ca

From playlist Volume and Surface Area