Important Formulas: Angles as Turns | Mathematics (Maths Mela) Class 5 - New NCERT PDF Download

Turns

• Full Turn: Turning completely around and coming back to the starting position.

• Half Turn: Turning halfway and facing the opposite direction.

• Quarter Turn: Turning one-fourth of a full turn, facing sideways.

• Rule:

  • 2 Half Turns = 1 Full Turn

  • 4 Quarter Turns = 1 Full Turn

  • 2 Quarter Turns = 1 Half Turn

Types of Angles

• Right Angle: 1/4 of a full turn. Looks like the corner of a book.

• Acute Angle: Less than a right angle. Sharp and small.

• Obtuse Angle: Bigger than a right angle but smaller than a straight angle.

• Straight Angle: 1/2 of a full turn. Forms a straight line.

Measuring Angles with Turns

Angles can be measured as fractions of a full turn.

• Examples:

  • 1/8 turn = Small angle

  • 2/8 turn = Right angle

  • 4/8 turn = Straight angle

  • 8/8 turn = Full turn

Directions of Turns

• Clockwise (CW): Same direction as a clock’s hands.

• Anti-clockwise (ACW): Opposite direction of clock’s hands.

Everyday Examples

• Taps → Quarter or half turn.

• Doors → Quarter or half turn.

• Scissors → Small turns.

• Giant Wheel → Full turns.