A protractor is a measuring instrument used in mathematics and geometry to measure angles. It is a flat, transparent, and usually circular tool marked with a scale of degrees or radians. The purpose of a protractor is to accurately determine the measurement of an angle between two lines or rays.
Typically, a protractor consists of a semicircular shape with a pivot point in the center that allows it to rotate freely. The scale is represented along the curved edge of the protractor, usually starting from zero and going up to 180 degrees or 360 degrees, depending on the type.
To use a protractor, one places the pivot point directly on the vertex of the angle to be measured. Then, the protractor is rotated until one of the lines or rays forming the angle aligns with the zero mark on the scale. The measurement can then be read off the scale where the other line or ray intersects.
Protractors are commonly made of plastic, clear acrylic, or sometimes metal. They are widely used in educational settings, particularly in geometry classes and for various geometric constructions. With the aid of a protractor, students can accurately measure and draw angles, facilitating the study of geometry and trigonometry.
Overall, a protractor is an essential tool in the field of mathematics, enabling the precise measurement and analysis of angles for a variety of practical applications.
