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polyhedron

a solid figure bounded by plane polygons or faces

face

cover the front or surface of

edge

a sharp side formed by the intersection of two surfaces of an object

vertex

the point of intersection of lines or the point opposite the base of a figure

regular polyhedron

any one of five solids whose faces are congruent regular polygons and whose polyhedral angles are all congruent

convex

curving or bulging outward

cross section

(physics) the probability that a particular interaction (as capture or ionization) will take place between particles

platonic solids

any one of five solids whose faces are congruent regular polygons and whose polyhedral angles are all congruent

tetrahedron

any polyhedron having four plane faces

octahedron

any polyhedron having eight plane faces

dodecahedron

any polyhedron having twelve plane faces

icosahedron

any polyhedron having twenty plane faces

prism

optical device having a triangular shape and made of glass or quartz

bases

compounds that reduce the concentration of hydrogen ions in a solution

lateral faces

the faces that are not the base of a parallelogram

right prism

each lateral edge is perpendicular to both bases

oblique prism

a prism that is not a right prism

surface area of a polyhedron

the sum of the areas of the faces of the polyhedron

lateral area of a polyhedron

the sum of the areas of its lateral faces

net

A two-dimensional pattern that can be folded to make a three-dimensional prism or pyramid

cylinder

a solid bounded by a cylindrical surface and two parallel planes (the bases)

right cylinder

a cylinder where the segment joining the centers of the bases is an altitude

lateral area of a cylinder

2πrh

surface area of a cylinder

2πrh+2πr²

pyramid

a massive memorial with a square base and four triangular sides

regular pyramid

a pyramid whose base is a regular polygon and whose lateral faces are congruent isosceles triangles

circular cone

has a circular base and a vertex that is not in the same plane as the base

lateral surface of a cone

pi r l

right cone

A cone in which a perpendicular line drawn from the base to the tip (vertex) passes through the center of the base

volume of a solid

lwh

sphere

any spherically shaped artifact

center of a sphere

The point inside a sphere that is the same distance from every point on the sphere.

radius of a sphere

a segment that has one endpoint at the center and the other endpoint on the sphere

chord of a sphere

a segment whose endpoints are on the sphere

diameter of a sphere

chord that contains the center

great circle

a circular line on the surface of a sphere formed by intersecting it with a plane passing through the center

hemisphere

either half of the cerebrum

similar solids

solids with the same shape and all their corresponding dimensions are proportional