A, the characteristics of the cylinder:

1, two circular faces of a cylinder are called bottom faces, the surrounding faces are called side faces, the bottom face is flat, and the side faces are curved faces.

2. Height of cylinder: The distance between two bottom surfaces of cylinder is called height. The number of columns is unclear.

3. The side development diagram of the cylinder: the side of the cylinder is rectangular after being developed along the height, the length of the rectangle is equal to the circumference of the bottom of the cylinder, and the width of the rectangle is equal to the height of the cylinder. When the perimeter and height of the bottom are equal, the edge height is square after expansion.

4. lateral area of a cylinder = perimeter of the bottom × height, that is, S-side =Ch or 2π r× h.

5. The surface area of a cylinder = lateral area of the cylinder+bottom area ×2, that is, S table =S side +S bottom ×2 or 2π r× h+2π r2.

6. The volume of the cylinder = the bottom area of the cylinder × the height, that is, V=sh or π R2× H..

7. There are two ways to circle a rectangle into a cylinder, and there are generally two ways to rotate a rectangle.

(One-to-one method: more materials are actually used than the calculated results. Therefore, when you want to keep numbers, the omitted digits are 4 or less, and you must go forward 1. This approximate method is called step-by-step method. )

Second, the characteristics of the cone:

1, the cone has only one bottom, and the bottom is a circle. The side of a cone is a curved surface.

2. The distance from the apex of the cone to the center of the bottom is the height of the cone. The cone has only one height. (Measuring the height of the cone: firstly, lay the bottom of the cone flat, place a flat plate horizontally on the top of the cone, and measure the distance between the flat plate and the bottom vertically. )

3. Enlarge the side of the cone to get a sector. 4. The volume of a cone is equal to one third of the volume of a cylinder with the same height as its bottom surface, that is, V-cone =Sh or V-Cone = π R2× H..

5. Common cylindrical cone solutions: ①. Road surface area (transverse area) that the road roller has passed; (2) The roller exceeds the length of the road surface (bottom perimeter); (3) Bucket iron (side area and bottom area); (4) Chef's hat (side area and bottom area); Ventilation pipe (side area).

6. Characteristics of cylinders and cones

Cylindrical cone

The two bottom surfaces are exactly the same, and they are both round. The bottom surface is round.

The side cut along the height is rectangular after expansion. Curved surface, cut along a line segment on the circumference of the vertex and the bottom surface, is fan-shaped after expansion.

There are countless distances between the two bottom surfaces. There is only one distance between the vertex and the center of the bottom surface.