Cone volume: V= bottom area × height ÷3
Side area of cylinder: S-side = bottom circumference × height.
Surface area of cylinder: S table = lateral area +2 bottom area.
Letters indicate:
Cylinder volume: V=sh
Cone hole volume: V=sh÷3
Cylindrical lateral area: S=ch/2πrh/πdh.
Surface area of cylinder: s=ch+2πr?
pillar; mainstay
Lateral area of a cylinder = bottom circumference × height (bottom circumference, you know, the circumference of a circle (2π r) or (π d)).
The surface area of a cylinder =2 base areas+1 lateral area (base area, you know, the area of a circle (π r×r) or (π (d÷2)×(d÷2) (don't forget × 2, because there are 2 base areas! ))
Volume of cylinder = bottom area × height (Sh) (this should be understood! )
The bottom area of a cylinder = the area of a circle (π r×r) or (π (d÷2)×(d÷2))
circular cone
Surface area may not be learned!
The area of the base = the area of the circle (π r×r) or (π (d÷2)×(d÷2) (it has only one base! )
Volume = 1/3× volume of a cylinder with the same height as its bottom surface = 1/3× area of its bottom surface× height = 1/3sh (the volume of a cone is equal to 1/3 of the volume of a cylinder with the same height as its bottom surface).
Description:
"π" (pà i) is an infinite circulating decimal, π = 3. 1415926535 ... π should be kept with 2 decimal places, and π should be 3.14.
"R" is the radius of the circle and "D" is the diameter of the circle. In the same or equal circle, R is 1/2 of D, D is twice of R, "S" is the area, and "H" is the height. The sum of the areas of all surfaces of an object is called its surface area. The size of the space occupied by an object is called its volume.
Provide:
When calculating the perimeter and area of a circle or the perimeter and area of the bottom, I have many discounts related to this.
The circumference of a circle or the circumference of the bottom.
1×π =3. 14
2×π =6.28
3×π =9.42
4×π = 12.56
5×π = 15.7
6×π = 18.84
7×π =2 1.98
8×π =25. 12
9×π =28.26
10×π =3 1.4
The area of a circle or the area of its base.
π× 1× 1=3. 14
π×2×2 = 12.56
π×3×3 =28.26
π×4×4 =50.24
π×5×5 =78.5
π×6×6 = 1 13.04
π×7×7 = 153.86
π×8×8 =200.96
π×9×9 =254.34
π× 10× 10 =3 14
Tip:
It's called a cylinder, not a cylinder. Don't use the word "body" Don't call it wrong!
Ask questions:
You should know a lot. Do the problem I gave you!
1. Find the surface area and volume of a cylinder, where r is 20cm and h and h are 30cm.
2. A cone, where d is 10cm and h is 20, find the bottom area and volume.
There is a fixed line and a moving line in the same plane. When the plane rotates around this fixed line, the surface formed by this moving line is called the revolution surface, the fixed line is called the axis of the revolution surface, and this moving line is called the generatrix of the revolution surface. If the generatrix is a straight line parallel to the axis, then the generated surface of revolution is called a cylindrical surface. If two planes perpendicular to the axis are used to cut the cylindrical surface, then the geometry surrounded by these two sections and the cylindrical surface is called a straight cylinder, which is called cylinder for short.
A cylinder consists of two bottoms and one side.
The two bottom surfaces of a cylinder are exactly the same two circles.
The distance between the two bottom surfaces is the height of the cylinder.
Cylinders have countless heights and axes of symmetry.
The side of a cylinder is a curved surface.
Side area of cylinder = bottom circumference x height.
Surface area of cylinder = side area+bottom area x2.
Volume of cylinder = bottom area x height
If V represents the volume of a cylinder, S represents the bottom area of the cylinder, and H represents the height of the cylinder, then the volume formula of the cylinder can be written as: V=Sh.
The volume is three times that of a cone with equal base and equal height.