No, a cone is not a Platonic solid. The Platonic solids are the five regular polyhedra: tetrahedron, cube, octahedron, dodecahedron, and icosahedron.
Start with a regular tetrahedron (triangular based pyramid). As you increase the number of sides in the base of the pyramid, the shape becomes more and more like a right cone. In the limit, the base tends to a polygon with an infinite number of sides - a circle, and the pyramid tends to a right cone.
It isn't a cone at all, technically or otherwise, by definition. A cone has a circular base; a pyramid, a polygonal one. In fact I think it's strictly only a pyramid if it has a quadrilateral base - anything else being a "~hedron" where the "~" part describes the number of faces, such as the Tetrahedron (4 triangular faces).
Well, a tetrahedron has four sides. A regular tetrahedron is a triangular pyramid.
A tetrahedron must be plane faced and so, it is just an ordinary tetrahedron.
You could classify a regular tetrahedron, which is a platonic sold, as a cone.
No, a cone is not a Platonic solid. The Platonic solids are the five regular polyhedra: tetrahedron, cube, octahedron, dodecahedron, and icosahedron.
The most simple pyramid is a tetrahedron. This pyramid has four faces, all triangles. If the pyramid was a cone then it could have two faces.
Start with a regular tetrahedron (triangular based pyramid). As you increase the number of sides in the base of the pyramid, the shape becomes more and more like a right cone. In the limit, the base tends to a polygon with an infinite number of sides - a circle, and the pyramid tends to a right cone.
I am not a tetrahedron!
hemisphere
It isn't a cone at all, technically or otherwise, by definition. A cone has a circular base; a pyramid, a polygonal one. In fact I think it's strictly only a pyramid if it has a quadrilateral base - anything else being a "~hedron" where the "~" part describes the number of faces, such as the Tetrahedron (4 triangular faces).
Some examples of solids are cube, sphere, cylinder, cone, pyramid, prism, tetrahedron, dodecahedron, octahedron, icosahedron, torus, cuboid, rhombic dodecahedron, ellipsoid, oloid, trapezohedron, truncated cone, truncated cuboctahedron, truncated dodecahedron, truncated icosahedron.
A tetrahedron has 4 faces.
Well, a tetrahedron has four sides. A regular tetrahedron is a triangular pyramid.
A tetrahedron must be plane faced and so, it is just an ordinary tetrahedron.
He faced a tetrahedron question in the exam paper. This is a sample sentence using the word tetrahedron.