When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Tetrahedron - Wikipedia

    en.wikipedia.org/wiki/Tetrahedron

    The tetrahedron is the three-dimensional case of the more general concept of a Euclidean simplex, and may thus also be called a 3-simplex. The tetrahedron is one kind of pyramid, which is a polyhedron with a flat polygon base and triangular faces connecting the base to a common point.

  3. Trigonometry of a tetrahedron - Wikipedia

    en.wikipedia.org/wiki/Trigonometry_of_a_tetrahedron

    The 12 face angles - there are three of them for each of the four faces of the tetrahedron. The 6 dihedral angles - associated to the six edges of the tetrahedron, since any two faces of the tetrahedron are connected by an edge. The 4 solid angles - associated to each point of the tetrahedron.

  4. Tetrahedral number - Wikipedia

    en.wikipedia.org/wiki/Tetrahedral_number

    A pyramid with side length 5 contains 35 spheres. Each layer represents one of the first five triangular numbers. A tetrahedral number, or triangular pyramidal number, is a figurate number that represents a pyramid with a triangular base and three sides, called a tetrahedron.

  5. Simplex - Wikipedia

    en.wikipedia.org/wiki/Simplex

    The tetrahedron is the 3-simplex, a simple shape that requires three dimensions. ... This formula is particularly useful when is the origin. The expression =! [ ...

  6. Solid angle - Wikipedia

    en.wikipedia.org/wiki/Solid_angle

    Just as the magnitude of a plane angle in radians at the vertex of a circular sector is the ratio of the length of its arc to its radius, the magnitude of a solid angle in steradians is the ratio of the area covered on a sphere by an object to the square of the radius of the sphere. The formula for the magnitude of the solid angle in steradians is

  7. Heron's formula - Wikipedia

    en.wikipedia.org/wiki/Heron's_formula

    Heron's formula is a special case of Brahmagupta's formula for the area of a cyclic quadrilateral. Heron's formula and Brahmagupta's formula are both special cases of Bretschneider's formula for the area of a quadrilateral. Heron's formula can be obtained from Brahmagupta's formula or Bretschneider's formula by setting one of the sides of the ...

  8. Trirectangular tetrahedron - Wikipedia

    en.wikipedia.org/wiki/Trirectangular_tetrahedron

    A trirectangular tetrahedron with its base shown in green and its apex as a solid black disk. It can be constructed by a coordinate octant and a plane crossing all 3 axes away from the origin (x>0; y>0; z>0) and x/a+y/b+z/c<1. In geometry, a trirectangular tetrahedron is a tetrahedron where all three face angles at one vertex are right angles.

  9. Cauchy stress tensor - Wikipedia

    en.wikipedia.org/wiki/Cauchy_stress_tensor

    The stress vectors acting on the faces of the tetrahedron are denoted as T (e 1), T (e 2), and T (e 3), and are by definition the components σ ij of the stress tensor σ. This tetrahedron is sometimes called the Cauchy tetrahedron. The equilibrium of forces, i.e. Euler's first law of motion (Newton's second law of motion), gives: