Cylinder

Cylinder Facts
Notice these interesting things:
	It has a flat base and a flat top
	The base is the same as the top, and also in-between
	It has one curved side
	Because it has a curved surface it is not a polyhedron.

And for reference:
	Surface Area = 2 × π × r × (r+h)
	Surface Area of One End = π × r² Surface Area of Side = 2 × π × r × h
	Volume = π × r²× h

Instructions: In "spin" mode it freely spins and will respond to your mouse. In "drag" mode it stops spinning and you can use your mouse to move it. If you cannot see the animation at all, you will need to install "Flash Player".

An object shaped like a cylinder is said to be cylindrical

Volume of a Cone vs Cylinder

The volume formulas for cones and cylinders are very similar:

The volume of a cylinder is:	π × r²× h
The volume of a cone is:	π × r²× (h/3)

So, the only difference is that a cone's volume is one third (¹/₃) of a cylinder's.

So, in future, order your ice creams in cylinders, not cones, you get 3 times more!

It Doesn't Have to Be Circular

Usually when we say Cylinder we mean a Circular Cylinder, but you can also have Elliptical Cylinders, like this one:

You can even have stranger cylinders: if the cross-section is curved and is the same from one end to the other, then it will still be a cylinder.

More Cylinders