Draw a straight line on the paper, which will be the bottom of the corner.
Mark a point on the straight line with a ruler, which will be the vertex of the angle.
From the vertex, draw a straight line with a ruler and intersect with the original straight line to form an angle.
You can measure the angle with a protractor.
When teaching children to draw corners, you can imitate the steps in the demonstration tutorial and encourage them to try to draw corners themselves. At the same time, they can pay attention to keep the ruler straight and use the protractor to measure the angle accurately.
Knowledge expansion:
Angle is a basic concept in mathematics and geometry, which represents the included angle between two rays in a geometric figure. The size of an angle can be expressed in degrees or radians.
In plane geometry, an angle usually consists of two rays or line segments. The common endpoint of these two rays is called the vertex of the angle, and these two rays are called the edge of the angle. According to the definition, an angle can be regarded as a plane part between two rays drawn from a point.
The size of an angle can be expressed in degrees or radians. A complete circle is 360 degrees in degrees, so the right angle is 90 degrees. In radians, a complete circle is 2π radians, so a right angle is π/2 radians.
Angle is a very important concept in trigonometric function. Trigonometric functions such as sine, cosine and tangent are all related to angle. For example, sine function sin(x) represents the sine value of angle x, cosine function cos(x) represents the cosine value of angle x, and tangent function tan(x) represents the tangent value of angle X.
In addition to the common angle system, there is also a system called radian, which represents the angle with the radius of the circle as the benchmark length unit. One radian equals an angle of 57.3, so a complete circle is 2π radians. In the polar coordinate system, the position of a point can be determined by distance and angle, where the angle is expressed in radians.
In practical application, the concept of angle is widely used in various fields, including engineering, machinery, physics, astronomy, geography and so on. For example, in mechanical manufacturing, the precision control of angle is very important; In physics, concepts such as angular velocity and angular momentum all involve angle; In astronomy, the concept of angle is often used in the position and movement of stars.
In a word, angle is a basic concept in mathematics and geometry, which represents the included angle between two rays in a geometric figure. The angle can be expressed in degrees or radians, which is widely used in various fields.