• Algebra
• Trigonometry
• Geometry
• Calculus

Sense of an angle

Definition

The direction of rotation of a ray from its initial position to final position is called sense of angle.

An angle is usually formed by a ray by rotation but the rotation of a ray is possible geometrically either clockwise or anticlockwise to form an angle geometrically. To understand how it is formed geometrically, the direction of rotation of a ray to form an angle is denoted by either plus sign or minus sign.

The plus sign or minus sign are actually written before the angle.

1. A plus sign $(+)$ or without a plus sign before the angle represents that the angle is made by a ray in anticlockwise direction.
2. A minus sign $(-)$ before the angle represents that the angle is made by a ray in clockwise direction.

The symbolic representation senses how the angle is formed geometrically.

Classification

According to concept of sense of angle, the angles are classified into two types.