A solid that has a circular
and a single
A cone is a solid that has a circular base and a a single vertex. If the vertex is over the center of the base, it is called a right cone. If it is not, it is called an oblique cone. An object that is shaped like a cone is said to be 'conical'.
Volume of a cone
The volume of a cone is given by the formula
where r is the radius of the circular base, and h is the height - the perpendicular distance from the base to the vertex.
For more on this see Volume of a cone
Surface area of a cone
The surface area of a cone is given by the formula
Where r is the radius of the circular base, and s is the
slant height of the cone.
For more, see Surface area of a cone
Right and Oblique cones
- If the apex is directly over the center of the base as it is above, it is called a right cone.
- If the apex is not over the center of the base, it is called an oblique cone. See
Oblique cone definition.
Relationship to a pyramid
Another way to think of a cone is as a pyramid with an infinite number of faces. In the figure below is a pyramid with 8 faces. If you keep clicking on 'more', you will see that is looks more and more like a cone.
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