MathematicsClass 6Basic Geometrical Ideas
Angles
Defining angles formed by two rays sharing a common endpoint along with their interior and exterior.
Class 6 · MathematicsCBSE & ICSE SOF IMO
Definition
An angle is formed when two rays diverge from a common starting point called the vertex. The two rays making up the angle are called its arms. Angles are measured in degrees using a protractor.
Worked examples
1
The space between the two hands of a clock at 3 o'clock forms an angle.
2
The corner of a book page forms a right angle.
3
Opening a door creates changing angle measurements between the door and the wall.
Common mistakes
- • Measuring an angle from the wrong scale on the protractor (mixing up the inner and outer scales).
- • Confusing the length of the ray arms with the actual size of the angle.