sphere

Table of Contents

Introduction References & Edit History Related Topics

Images

The normal, or perpendicular, at each point of a surface defines the corresponding tangent plane, and vice versa.

sphere with circumscribing cylinder

Discover

Aspirin pills.

7 Drugs that Changed the World

Close up of books. Stack of books, pile of books, literature, reading. Homepage 2010, arts and entertainment, history and society

12 Novels Considered the “Greatest Book Ever Written”

Portrait of a mountain gorilla at a short distance. gorilla close up portrait.The mountain gorilla (Gorilla beringei beringei)

Falling Stars: 10 of the Most Famous Endangered Species

Thumbnail for flags that look alike quiz Russia, Slovenia, Iceland, Norway

Flags That Look Alike

Illustration for Demystified "How Dangerous is Quicksand"

How Deadly Is Quicksand?

Berries and leaves of the bittersweet nightshade (Solanum dulcamara) plant. Poisonous plant

7 of the World’s Deadliest Plants

The Battle of New Orleans, by E. Percy Moran, c. 1910. Andrew Jackson, War of 1812.

26 Decade-Defining Events in U.S. History

sphere: Related Content

Written and fact-checked by The Information Architects of Encyclopaedia Britannica

Photos

The normal, or perpendicular, at each point of a surface defines the corresponding tangent plane, and vice versa.

sphere with circumscribing cylinder

See All Images →

Topics

Poincaré conjecture spherical triangle Ewald’s sphere pseudosphere geodesic rhumb line ellipsoid cone paraboloid hyperboloid cylinder

Key People

Archimedes

Archimedes

Greek mathematician

Menelaus of Alexandria

Greek mathematician

Quiz

Equations written on blackboard

Numbers and Mathematics