More geometry
Angles and turns
An angle is the space between two lines that meet. When we turn, we make an angle. Let's learn about quarter turns, half turns, full turns and right angles.
What is an angle?
An angle is the space between two lines that meet at a point. When something turns, it makes an angle. Look at a clock: the minute hand and the hour hand make an angle where they meet.
Quarter, half and full turns
ā¢ A quarter turn is a small turn. ā¢ A half turn is two quarter turns. ā¢ A full turn is four quarter turns and takes you all the way around. Two half turns in the same direction make a full turn. After a full turn you face the same way you started.
Right angles
A quarter turn in any direction is called a right angle. The corner of a book or a window is a right angle. A half turn is two right angles, and a full turn is four right angles.
Clockwise and anticlockwise
Clockwise is the direction the hands of a clock move. Anticlockwise is the opposite direction. We can turn clockwise or anticlockwise.
Worked examples
A quarter turn is a right angle
- Start facing one way.
- Make one quarter turn.
Answer: The turn you made is a right angle.
A full turn is four quarter turns
- Make a quarter turn: that is 1.
- Keep turning the same way: 2, then 3, then 4 quarter turns.
Answer: Four quarter turns make one full turn, and you face the same way as the start.
Clockwise or anticlockwise
- Look at which way the clock hands move ā that is clockwise.
- The other way is anticlockwise.
Answer: Clockwise is the way clock hands move; anticlockwise is the opposite.
A half turn is two right angles
- Make one quarter turn (one right angle).
- Make another quarter turn the same way (another right angle).
Answer: Two right angles together make a half turn.
Where you see this in real life
- The hands of a clock turn clockwise and make angles.
- Turning a door handle a quarter turn to open a door.
- Turning a corner when you walk to the end of a path.
- Spinning all the way round is a full turn.
Key words
- Angle
- The space between two lines that meet.
- Turn
- Moving around a point, like a clock hand.
- Quarter turn
- A small turn, the same as one right angle.
- Half turn
- Two quarter turns, or two right angles.
- Full turn
- Four quarter turns, all the way around.
- Right angle
- A quarter turn, like the corner of a book.
- Clockwise
- The direction the hands of a clock move.
- Anticlockwise
- The opposite direction to clockwise.