**Types of Angles Based on Turns:**
**Full Turn** = Complete rotation back to start = 360°
**Half Turn (Straight Angle)** = 1/2 turn = 180°
**Quarter Turn (Right Angle)** = 1/4 turn = 90°
**Acute Angle** = Less than 1/4 turn (less than 90°)
**Obtuse Angle** = More than 1/4 turn but less than 1/2 turn (between 90° and 180°)
**Important Turns:**
1/8 turn = half of a quarter turn
3/8 turn = more than a quarter turn
5/8 turn = more than a half turn
1/6 turn = one-sixth of full circle
1/12 turn = one-twelfth of full circle
**Clock Minute Hand:**
15 minutes = 1/4 turn
30 minutes = 1/2 turn
45 minutes = 3/4 turn
60 minutes = full turn
**Directions:**
**Clockwise** = Direction clock hands move (top → right → bottom → left)
**Anti-clockwise** = Opposite direction
**Diagrams to Remember:** Angle measuring tool with folded circle, clock faces showing different minute hand positions, gymnast poses showing acute/right/obtuse angles.
**Don't Confuse:** Acute angle (small, pointy) is NOT the same as obtuse angle (wider). A 1/4 turn makes a right angle, not an acute angle.
Q1. When the minute hand of a clock moves from 12 to 3, it makes a _______ turn.
Answer: C — From 12 to 3 is 15 minutes, which is 1/4 of the 60-minute circle, so it is a quarter turn.
Q2. Which angle is formed by a turn that is less than a quarter turn?
Answer: B — An acute angle is defined as any turn less than a quarter turn, making it small and pointed.
Q3. If Reema makes 2 quarter turns in the same direction, she has made a _______ turn.
Answer: C — 1/4 + 1/4 = 2/4 = 1/2, which is a half turn.
Q4. The direction in which clock hands move is called _______.
Answer: C — Clockwise is the standard term for the direction that clock hands move from top to right to bottom.
Q5. An obtuse angle is formed by a turn that is:
Answer: C — An obtuse angle is specifically between a quarter turn and a half turn, making it wider than a right angle.
Q6. Looking at a door opening from closed position, the maximum turn it can make is:
Answer: C — A typical door opens more than 90 degrees but less than 180 degrees, forming an obtuse angle.
Q7. When the minute hand moves by 30 minutes, it has made a _______ turn of the circle.
Answer: C — 30 minutes is exactly half of 60 minutes, so the minute hand makes a 1/2 turn.
Q8. Which object can make a full turn?
Answer: B — A tap can turn continuously and make a full complete turn, unlike scissors or clips which have limited movement.
Q9. Two acute angles added together can form an:
Answer: A — Two small turns (acute angles) together can make a larger turn that is between 1/4 and 1/2, which is an obtuse angle.
Q10. The angle marking in the house diagram is a right angle. This means it is a turn of:
Answer: C — A right angle is always formed by exactly a 1/4 turn, which is 90 degrees of a full circle.
What is a full turn?
A full turn is when something rotates completely and comes back to its starting position, like a minute hand on a clock after 60 minutes.
What is a quarter turn?
A quarter turn is 1/4 of a full turn, and it creates a right angle, like when a door opens 90 degrees from the wall.
What is a half turn?
A half turn is 1/2 of a full turn, and it creates a straight angle, like when you turn around completely to face the opposite direction.
What is an acute angle?
An acute angle is formed by a turn that is less than a quarter turn, and it looks like a small opening, like the angle between two fingers slightly apart.
What is an obtuse angle?
An obtuse angle is formed by a turn that is more than a quarter turn but less than a half turn, like the angle at the top of a mountain shape.
What does clockwise mean?
Clockwise is the direction that the hands of a clock move, from top to right to bottom to left.
What does anti-clockwise mean?
Anti-clockwise is the opposite direction to clockwise, moving from top to left to bottom to right.
How many minutes does a 1/4 turn of the minute hand equal?
A 1/4 turn of the minute hand equals 15 minutes because the minute hand completes a full turn in 60 minutes.
What do two quarter turns equal?
Two quarter turns equal one half turn, which makes a straight angle.
What tool can you make to measure angles?
You can make an angle measuring tool by cutting a circle from tracing paper, folding it into equal parts, and attaching a straw at the center.
What is a quarter turn, and what angle does it make? [1 mark]
A quarter turn is 1/4 of a full circle. It creates a right angle, which you see when a door opens 90 degrees from a wall.
If the minute hand of a clock moves from 12 to 6, how many turns has it made? Name the angle formed. [2 marks]
From 12 to 6 is 30 minutes, which is half of 60 minutes. A half turn creates a straight angle.
Explain with an example from your home how clockwise and anti-clockwise movements are different. Give one example of each. [3 marks]
Clockwise is the direction clock hands move. Anti-clockwise is the opposite. Examples: opening a tap is clockwise (usually), unscrewing a lid might be anti-clockwise. Choose real objects you see at home.
You have made an angle measuring tool by folding a circle into 8 equal parts. (a) Show how you would measure a 3/8 turn using your tool. (b) Is a 3/8 turn an acute angle or obtuse angle? (c) What would be the measure if you added 2/8 turn and 3/8 turn together? [5 marks]
For (a), count 3 parts on your folded circle. For (b), check if 3/8 is less than 1/4 (acute) or between 1/4 and 1/2 (obtuse). For (c), add the fractions: 2/8 + 3/8 = 5/8, then check what angle this makes.
True or False? (a) A half turn and two quarter turns are the same. (b) An obtuse angle is smaller than a right angle. Give reasons for your answers. [2 marks]
For (a), calculate: two quarter turns = 2 × (1/4) = 1/2, so they are the same. For (b), remember that obtuse angles are wider (larger) than right angles, not smaller.
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