Among them, a circle has two bottom surfaces, and a rectangle or a square is a side surface.

Extended data:

The two circular faces of a cylinder are called bottom faces, and the surrounding faces are called side faces. A cylinder consists of two bottom surfaces and one side surface.

The two bottom surfaces of a cylinder are exactly the same two circular surfaces. The distance between the two bottom surfaces is the height of the cylinder.

The side surface of the cylinder is a curved surface, and the development diagram of the side surface of the cylinder is a rectangle, a square or a parallelogram (diagonal cutting). Transverse area of cylinder = X height of bottom circumference, i.e.:

S transverse area =Ch=2πrh.

Bottom circumference C=2πr=πd

Surface area of cylinder = lateral area+bottom area x2 = ch+2π r 2 = 2π r (r+h).

Volume of cylinder = bottom area x height: that is, V=S bottom area x h = (π× r× r) h.

The volume of a cylinder with equal base and equal height is three times that of a cone.

A parallelogram can enclose a cylinder.

Surface area of cylinder = side area+bottom area x2.

Divide the cylinder into two identical parts along the diameter of the bottom surface, and each part is called a semi-cylinder. At this time, compared with the original cylinder, the surface area =πr(r+h)+2rh, and the volume is half of the original.

The axial section of a cylinder is a rectangle with a diameter of x and the section is a circle with the same bottom.

Reference from Baidu Encyclopedia: Cylinder.