. How many edges does a cuboid have? Count, please师：长方体有多少条棱？数数看。.

Free cube templates to print, cut out, and assemble into a three-dimensional paper cube. Share Tweet Pin it. Template 1 - Makes a 2¼' Cube. Template 2 - Makes a 1½' Cube. Open any of the printable files above by clicking the image or the link below the image. Total Surface Area of a Cuboid Calculator. A cuboid is a three-dimensional geometric solid shape with 6 faces. All corners of a cuboid are right angles and opposite faces or sides are equal. In other words, a cuboid is a solid figure bounded by six faces, forming a convex polyhedron. It can also be called as a rectangular cuboid.

Measure the length, width and height of the cuboid量出指定的长方体的长、宽、高。. Touch the length, the width and the height of a cuboid用手摸一摸长方体的长、宽、高。. Every face of a cuboid must be a rectangle长方体每个面一定是长方形。.

The third was a human - sized cuboid第三种则是和真人大小一致的立方体。. The cuboid has faces, edges and points生：长方体有面、棱、顶点。. Demonstsatos for showing the edge liness and the area of the cuboid长方体棱长与表面积演示器. Now let ' s study cuboids by their faces, edges and points下面我们就面、棱、顶点研究长方体。.

Count how many points a cuboid has师：数一数长方体有几个顶点？. Touch the cuboid. What features does the cuboid have师：用手摸一摸长方体发现长方体有什么特征？. 更多例句： 1. In geometry, a cuboid is a convex polyhedron bounded by six quadrilateral faces, whose polyhedral graph is the same as that of a cube.

While some mathematical literature refers to any such polyhedron as a cuboid, other sources use 'cuboid' to refer to a shape of this type in which each of the faces is a rectangle (and so each pair of adjacent faces meets in a right angle); this more restrictive type of cuboid is also known as a rectangular cuboid, right cuboid, rectangular box, rectangular hexahedron, right rectangular prism, or rectangular parallelepiped.

In geometry, a cuboid is a convex polyhedron bounded by six quadrilateral faces, whose polyhedral graph is the same as that of a cube. While mathematical literature refers to any such polyhedron as a cuboid,^[1] other sources use 'cuboid' to refer to a shape of this type in which each of the faces is a rectangle (and so each pair of adjacent faces meets in a right angle); this more restrictive type of cuboid is also known as a rectangular cuboid, right cuboid, rectangular box, rectangular hexahedron, right rectangular prism, or rectangular parallelepiped.^[2]

General cuboids[edit]

By Euler's formula the numbers of faces F, of vertices V, and of edges E of any convex polyhedron are related by the formula F + V = E + 2. In the case of a cuboid this gives 6 + 8 = 12 + 2; that is, like a cube, a cuboid has 6 faces, 8 vertices, and 12 edges.Along with the rectangular cuboids, any parallelepiped is a cuboid of this type, as is a square frustum (the shape formed by truncation of the apex of a square pyramid).

Rectangular cuboid[edit]

In a rectangular cuboid, all angles are right angles, and opposite faces of a cuboid are equal. By definition this makes it a right rectangular prism, and the terms rectangular parallelepiped or orthogonal parallelepiped are also used to designate this polyhedron. The terms 'rectangular prism' and 'oblong prism', however, are ambiguous, since they do not specify all angles.

The square cuboid, square box, or right square prism (also ambiguously called square prism) is a special case of the cuboid in which at least two faces are squares. It has Schläfli symbol {4} × { }, and its symmetry is doubled from [2,2] to [4,2], order 16.

The cube is a special case of the square cuboid in which all six faces are squares. It has Schläfli symbol {4,3}, and its symmetry is raised from [2,2], to [4,3], order 48.

If the dimensions of a rectangular cuboid are a, b and c, then its volume is abc and its surface area is 2(ab + ac + bc).

The length of the space diagonal is

${\displaystyle d=\sqrt{a^2+b^2+c^2}.}$

Cuboid shapes are often used for boxes, cupboards, rooms, buildings, containers, cabinets, books, a sturdy computer chassis, printing devices, electronic calling touchscreen devices, washing and drying machines, etc. Cuboids are among those solids that can tessellate 3-dimensional space. The shape is fairly versatile in being able to contain multiple smaller cuboids, e.g. sugar cubes in a box, boxes in a cupboard, cupboards in a room, and rooms in a building. Pit people ending.

A cuboid with integer edges as well as integer face diagonals is called an Euler brick, for example with sides 44, 117 and 240.A perfect cuboid is an Euler brick whose space diagonal is also an integer. It is currently unknown whether a perfect cuboid actually exists.

Nets[edit]

The number of different nets for a simple cube is 11, however this number increases significantly to 54 for a rectangular cuboid of 3 different lengths.^[3]

See also[edit]

References[edit]

1. ^Robertson, Stewart Alexander (1984). Polytopes and Symmetry. Cambridge University Press. p. 75. ISBN9780521277396.
2. ^Dupuis, Nathan Fellowes (1893). Elements of Synthetic Solid Geometry. Macmillan. p. 53. Retrieved December 1, 2018.
3. ^Steward, Don (May 24, 2013). 'nets of a cuboid'. Retrieved December 1, 2018.

External links[edit]

• Weisstein, Eric W.'Cuboid'. MathWorld.
• Rectangular prism and cuboid Paper models and pictures