Издательство: | Книга по требованию |
Дата выхода: | июль 2011 |
ISBN: | 978-6-1311-9018-6 |
Объём: | 92 страниц |
Масса: | 160 г |
Размеры(В x Ш x Т), см: | 23 x 16 x 1 |
High Quality Content by WIKIPEDIA articles! In geometry, a spherical wedge or ungula is a portion of a ball bounded by two plane semidisks and a spherical lune (termed the wedge's base). The angle between the radii lying within the bounding semidisks is the dihedral angle of the wedge ?. If AB is a semidisk that forms a ball when completely revolved about the z-axis, revolving AB only through a given ? produces a spherical wedge of the same angle ?. Beman (2008) remarks that "a spherical wedge is to the sphere of which it is a part as the angle of the wedge is to a perigon."[A] A spherical wedge of ? = ? radians (180°) is called a hemisphere, while a spherical wedge of ? = 2? radians (360°) constitutes a complete ball. The volume of a spherical wedge can be intuitively related to the AB definition in that while the volume of a ball of radius r is given by tfrac{4}{3} pi r^3, the volume a spherical wedge of the same radius r is given by frac{alpha}{2pi} cdot frac{4}{3} pi r^3 = frac{2}{3} alpha r^3
Данное издание не является оригинальным. Книга печатается по технологии принт-он-деманд после получения заказа.