Introduction of hectares:
The hectare is a metric drawing unit. Nickname: square meter, square hectare (easy to remember and convert). Symbol: Haha? . The hectare is the metric unit (international unit) of area. A piece of land with an area of one hectare is 10000 square meters.
Introduction of area unit:
The size of the plane figure occupied by objects is called their area. Area is the size of a plane figure. Area unit refers to the unit for measuring the surface size of an object.
The order from small to large is: mm? (square millimeters), centimeters? (square centimeter), dm? (square decimeter), m? (square meters), huh? (hectares), kilometers? (square kilometers). In the International System of Units (SI), the standard unit area is meters (square meters), and the area is a square area one meter long.
The size of the plane figure occupied by objects is called their area. Area is the size of a plane figure, square meters, square decimeters and square centimeters, which is a recognized unit of area and can be expressed as (m? ，dm？ ，cm？ )。
Area is a quantity indicating the degree of a two-dimensional figure or shape or plane layer in a plane. A surface region is a simulation on a two-dimensional surface of a three-dimensional object. Area can be understood as the amount of material with a given thickness, which is necessary to form a shape model. The area of a shape can be measured by comparing a fixed size shape with a square.
In the International System of Units (SI), the standard unit area is square meters (m2), and the area is a square area one meter long. The shape of an area of three square meters will be the same as that of three such squares. In mathematics, the unit square is defined as 1, and the area of any other shape or surface is a dimensionless real number.
Teaching objectives:
Understand the meaning of area and know the commonly used area units. Initially establish the area expressions of 1 cm2, 1 cm2 and 1 m2, and measure the area of the specified surface with cm2 and cm2. Cultivate students' observation ability, practical ability and generalization ability.