Introduction Of Angle -
Angles are geometric figures formed by two rays that share a common endpoint called a vertex. The two rays are called the sides of the angle. Angles are measured in degrees, with a full circle being 360 degrees. Angles can be classified according to their size or shape.
Some common types of angles include:
Angles are used in many fields, including mathematics, engineering, and physics, and are an important concept in trigonometry, which deals with the relationships between angles and sides of triangles.
- Two rays starting from a common point form an angle.
- The two rays are called the arms or sides of the angle.
- The meeting point of the arms of the angle is called the vertex.
- An angle is denoted by the symbol ∠.
- An angle is named by three capital letters. The letter at the vertex always comes in between the other two letters. The given angle is named as ∠ AOB or ∠ BOA. Vertex O is at the middle of P and R.
The unit for measuring angles is degree. The symbol for degree is °.
The ere are some type of angles are given below with picture for your better understanding -
1. ACUTE ANGLE :-
An angle whose measure is less than 90° is called an acute
Examples : 30°, 45°, 84°
2. RIGHT ANGLE :-
An angle whose measure is 90° is called a right angle.
3. OBTUSE ANGLE :-
An angle which measures more than 90° but less than 180° is called an obtuse angle.
Examples : 120°, 135°, 175°.
4. STRAIGHT ANGLE :-
An angle whose measure is 180° is called a straight angle.
5. REFLEX ANGLE :-
An angle whose measure is greater than 180° but less than 360° is called a reflex angle.
Examples : 210°, 195°, 340°
An angle whose measure is 360° is called a complete angle.