Because the central angle of a semicircle is 180 degrees, 180 parts are used to represent the semicircle, and each part represents 1 degree. A protractor is a tool for measuring angles. How to use the protractor: aim the center of the protractor at the vertex of the angle, aim the zero scale line of the protractor at one side of the angle, and then look at the corresponding scale on the other side, which is the degree of the angle.
Types of protractors: protractors are divided into mechanical and electronic types. Precautions for protractor: When using protractor, avoid sharp corners and draw or place heavy objects on protractor.
The difference between protractor and goniometer is as follows:
1, with different definitions: protractor is a tool for measuring angles, while goniometer is an instrument for detecting angles.
2. Different functions: the protractor can draw angles, measure angles, draw vertical lines and parallel lines, measure inclination, verticality and levelness, while the protractor only has the function of detecting angles.
3. Different use scenarios: protractors are mostly used in the field of mathematical geometry, while goniometers are mostly used in practical application fields such as engineering and technology.
The benefits of mathematics:
1. Mathematics is the basis of all re-education. Mathematics is an important channel to cultivate logical thinking.
2. Mathematics is a tool subject. It is the basis of learning other subjects, and it is also a subject to improve people's ability of judgment, analysis and understanding.
Math can make you think about any problem carefully. Not being confused, you can also let your brain reflect flexibly and deal with emergencies more rationally.
4. Mathematics is a pleasure. It also has its own fun.
Math can give you more abilities. Including observing experiments, collecting information, inductive analogy, intuitive judgment, logical reasoning, modeling and accurate calculation. These abilities are not only of great help to your study and life, but also can make you smarter.