NCERT Solutions Class 5 Mathematics Mela Chapter 03 Angles as Turns

Question. Use your paper fan to show different acute angles and obtuse angles.
Answer: You can open the paper fan to various widths to display different types of angles. When the fan opening is small - less than 90 degrees - it shows an acute angle. The two sticks of the fan form this narrow angle. When you open the fan further so the gap between the sticks becomes larger than 90 degrees but less than 180 degrees, you create an obtuse angle. You can adjust the fan to any position between fully closed and fully open to demonstrate all the different acute and obtuse angles you want to show.
In simple words: Open the fan a little bit to make a small acute angle. Open it more to make a bigger obtuse angle.

Exam Tip: Remember - acute angles are smaller than a right angle (90 degrees), and obtuse angles are larger than a right angle but smaller than a straight angle (180 degrees).

Question. You might have built houses using the hard covers of notebooks or cardboard pieces. Look at the angles marked in the house. What angles are you able to see in this house? Write your answers as right, acute or obtuse angle.
Answer: Looking at the house structure, you can identify several different types of angles at various points:
A: Obtuse Angle
B: Right Angle
C: Acute Angle
D: Acute Angle
E: Acute Angle
F: Right Angle
G: Right Angle
H: Obtuse Angle
In simple words: Houses have many angles - some are sharp (acute), some are perfect 90-degree corners (right), and some are wide open (obtuse).

Exam Tip: Look at the corner or join point carefully - measure or compare it with a right angle to decide if it is acute, right, or obtuse.

Question. Make a 5-sided shape with 2 right angles, 2 obtuse angles, and 1 acute angle in your notebook.
Answer: Draw a 5-sided figure (pentagon) where each corner has a specific type of angle. Start by drawing two sides that meet at a right angle (90 degrees). From there, draw another pair of sides that meet at a right angle. Then create two corners with obtuse angles (wider than 90 degrees) by making the sides open more than a right angle. Finally, add one corner where the sides meet at an acute angle (narrower than 90 degrees). The shape will not be regular - some corners will be very open while one will be quite narrow. Make sure when you add up all five angles together, they total 540 degrees, which is the sum for any 5-sided shape.
In simple words: Draw a shape with five corners - two that are 90 degrees, two that are wider than 90 degrees, and one that is smaller than 90 degrees.

Exam Tip: Use a ruler and protractor or angle tools to measure each angle you draw, ensuring you have the correct types in the correct places.

Question. Look at the angle formation between the legs of these gymnasts. Identify whether the angles are acute, obtuse, right or straight.
Answer: By examining the leg positions of the gymnasts in the image, you can spot different angle types. The gymnast at the top has legs positioned to form an acute angle - the space between the legs is small and pointed. The gymnasts on the left and right sides show obtuse angles - their legs are spread wide apart, creating an opening larger than 90 degrees. The gymnasts at the bottom have legs arranged to show right angles - the gap between their legs forms a perfect 90-degree angle. These positions show how the human body can create all these different angle types through movement and stretching.
In simple words: When gymnasts stretch their legs in different ways, the space between them makes acute, right, obtuse, and straight angles.

Exam Tip: Compare each angle position to a known right angle (like the corner of a square) to help you decide if it is smaller (acute), equal (right), or larger (obtuse).

Let Us Think

Question. In the following circles, the end points of 1/2, 1/4 and 1/8 turns are shown. Draw arrows to show the starting points.
Answer: For each circle shown, you need to work backwards from the end point arrow that is already drawn. When a 1/2 turn (or 180 degrees) is made, the starting point arrow should be directly opposite to the ending point arrow. For a 1/4 turn (or 90 degrees), the starting arrow should be positioned 90 degrees away from the ending arrow. For a 1/8 turn (or 45 degrees), the starting arrow should be 45 degrees away from where the arrow now points. Draw these starting point arrows on your paper to show where each rotation began before it ended at the position shown.
In simple words: If you know where something ended after a turn, you can figure out where it started by rotating backwards by that same amount.

Exam Tip: Always rotate in the opposite direction to find the starting point - if the turn was clockwise, rotate counter-clockwise to find where the arrow began.

Question 1. Guess the measures of each of the angles shown below. Then, check using your angle measuring tools. You may need to use a combination of measures. Also, state whether each of the angles is acute, right or obtuse.
Answer: Look at each angle carefully and try to estimate its size by comparing it to a right angle (90 degrees). Use a protractor, angle ruler, or other angle-measuring tool to find the exact measure. Some angles might be simple ones like 30 degrees or 60 degrees. Others might need you to add two measures together - for example, an angle might be 45 degrees + 30 degrees = 75 degrees. Once you measure, classify each angle as acute (less than 90 degrees), right (exactly 90 degrees), or obtuse (between 90 and 180 degrees). Record both the measurement in degrees and the angle type for each angle you measure.
In simple words: Guess how wide each angle opens, measure it with a tool, then say if it is small (acute), a perfect corner (right), or wide (obtuse).

Exam Tip: Use your angle-measuring tool carefully - line up the base line with one side of the angle and read where the other side of the angle crosses the scale.

Question 2. Guess the measure of the turns made by the arrow in each of the following cases. Verify with a combination of angle measuring tools.
Answer: For each arrow position shown, estimate how much the arrow has turned from its starting direction. Common turn amounts are 1/8 turn (45 degrees), 1/4 turn (90 degrees), 3/8 turn (135 degrees), 1/2 turn (180 degrees), 5/8 turn (225 degrees), 3/4 turn (270 degrees), and 7/8 turn (315 degrees). Verify your guess by using angle-measuring tools like protractors or angle rulers to find the exact measurement. You may need to use combinations - for example, some angles might be 1/4 turn plus 1/8 turn (or 135 degrees). Record your guesses first, then measure and compare them to see how close you were.
In simple words: Guess how far the arrow has spun, then measure it with your tools to check if you were right.

Exam Tip: Remember that a full turn is 360 degrees - use this to help you estimate parts of a turn like 1/4 (90 degrees) or 1/2 (180 degrees).

Question 3. Measure each angle in the given shapes. Write the measure of the angles in terms of turns and describe whether they are acute, obtuse or right angles.
Answer: For each shape provided, use a protractor or angle-measuring tool to find the degree measure of every angle. Then convert that degree measure into a fraction of a turn - for example, 90 degrees equals 1/4 turn, and 180 degrees equals 1/2 turn. To convert, divide the degree measure by 360 (a full turn). Once you have the angle measure in both degrees and turns, classify it: acute angles measure less than 90 degrees (less than 1/4 turn), right angles measure exactly 90 degrees (exactly 1/4 turn), and obtuse angles measure between 90 and 180 degrees (between 1/4 and 1/2 turn). Write all this information next to each angle in your diagram.
In simple words: Measure each angle with a tool, write it as a turn fraction, and say if it is small, big, or a perfect corner.

Exam Tip: To change degrees to turns, divide by 360 - so 90 degrees ÷ 360 = 1/4 turn, and 180 degrees ÷ 360 = 1/2 turn.

Question 4. Draw angles for the given measures of turns using the given lines.
Answer: You are given one line and a fraction of a turn to create. To draw the angle, place your protractor with its center point on the vertex (meeting point) of the given line. Align the base of the protractor with the given line. Find the degree measure by multiplying the turn fraction by 360 - for example, 1/8 turn equals 45 degrees, 1/4 turn equals 90 degrees, 1/2 turn equals 180 degrees. Mark the point at that degree measure on the protractor scale. Draw a second line from the vertex through that marked point. The angle between your original line and this new line is the angle you wanted to create. Label the angle with its turn measure and angle type (acute, right, or obtuse).
In simple words: Use a protractor to draw a second line that makes the right turn angle with the first line.

Exam Tip: Always align the protractor carefully at the vertex - small shifts can make your angle measure wrong.

Question 5. Draw the angles formed by the following turns in your notebook. 1/2 turn, 1/4 turn, 2/4 turn, 1/6 turn, 4/6 turn, 3/12 turn, 1/2 + 1/4 turn and 1/8 + 1/6 turn.
Answer: For each turn measurement given, convert it to degrees by multiplying by 360. A 1/2 turn equals 180 degrees, a 1/4 turn equals 90 degrees, and a 1/6 turn equals 60 degrees. Use a protractor to draw each angle. Start with a horizontal line as your base. Place the protractor's center at one end of the line. Mark the degree measure calculated above. Draw a ray (half-line) from the center through that mark. For compound turns like 1/2 + 1/4 turn, add them first (equals 3/4 turn or 270 degrees) then draw that single angle. Similarly, 1/8 + 1/6 turn requires finding a common denominator (24ths), adding to get 7/24 turn, converting to degrees, then drawing. Draw all these angles clearly and label each one with its turn fraction and degree measure.
In simple words: Turn each fraction into degrees, use your protractor to draw that angle, and label it.

Exam Tip: For adding turns, find a common denominator first - this makes the addition much clearer and less error-prone.

Question 6. Guess the measure of turns the minute hand of a clock makes in each of the following cases. The initial position of the minute hand is given. Draw the final position of the minute hand on the clock face. Discuss your reasoning in class.
Answer: For each starting position shown, determine the turn amount - this might be given as a fraction like 1/2 turn, 1/4 turn, or 3/12 turn. Convert the turn to minutes on a clock face (since the minute hand travels 6 degrees per minute, or one minute marking per 6 degrees). A 1/4 turn equals 90 degrees, which is 15 minutes on a clock. A 1/2 turn equals 180 degrees or 30 minutes. A 1/6 turn equals 60 degrees or 10 minutes. From the starting position shown, count forward or rotate the hand by the number of minute spaces equal to your turn measure. Draw the hand in its new position and label it. Verify your answer by checking that the new position makes sense given the starting point and the turn direction (clockwise or counter-clockwise).
In simple words: Look at where the minute hand starts, turn it by the amount you are told, and draw where it lands.

Exam Tip: On a clock, 15 minutes = 1/4 turn, 30 minutes = 1/2 turn, and 60 minutes = a full turn - memorize these to work faster.

Fun with Turns

Question 1. The children in a class are playing a game in which the teacher tells them the direction in which they should rotate. Complete the table by filling the direction the children will face on completing the given turns. The starting direction is given in the table.
Answer: Use the compass directions (North, South, East, West) and track the rotation. Starting from North and rotating two right angles clockwise means turning 90 degrees + 90 degrees = 180 degrees, which brings you to face South. Starting from South and rotating two right angles counter-clockwise also brings you to face North (each right angle is 90 degrees, so 180 degrees total rotation). Four right angles in any direction always complete a full 360-degree rotation, returning you to the starting direction. For mixed rotations like "3 right angles clockwise, 1/2 right angle clockwise, 1/2 right angle clockwise," add them (3.5 right angles = 315 degrees clockwise), which from South points you to South again. Work through each row carefully, tracking the total rotation degrees and which direction you end up facing.
In simple words: Each right angle turn is 90 degrees. Count the turns, add them up, and figure out which direction you will face.

Exam Tip: Draw a compass on paper and use your pencil to rotate and track - this visual method is much faster and more accurate than trying to calculate in your head.

Question 2. Padma is facing the toy shop. What place will she face if she takes a half turn clockwise? What other way can she turn to face the same place?
Answer: If Padma is facing the Toy Shop and makes a half turn (180 degrees) in the clockwise direction, she will rotate to face the opposite direction - which is the Ice Cream Shop. Another way for her to face the Ice Cream Shop is to turn half a turn in the counter-clockwise direction, which also equals 180 degrees and brings her to the same spot. Both paths lead to the same ending point because half a turn in either direction (clockwise or counter-clockwise) rotates you exactly 180 degrees. You could also describe turning one full turn (360 degrees) plus a half turn counter-clockwise, but the simplest alternative is just a half turn counter-clockwise.
In simple words: A half turn clockwise and a half turn counter-clockwise both spin you around to face the opposite direction.

Exam Tip: When asked "what other way," look for rotations that are equivalent - same total degrees but different direction or broken into different parts.

How does Class 5 Maths Mela Chapter 3 help in daily life?

Class 5 Maths Chapter 3 "Angles as Turns" is quite useful in everyday situations. It teaches students how to observe and measure rotations and angles that appear in common objects all around them. When you turn a tap, rotate a steering wheel, or open scissors, you are performing turns. Learning about turns also makes it easier to understand how a clock works. Understanding clockwise and counter-clockwise movements is needed when using many everyday tools and machines. This chapter makes students more aware of the world around them. They begin to spot angles everywhere - in doorways, windows, toys, and sports activities. Building this knowledge creates a strong foundation for more advanced geometry study in later classes. It also helps with problem-solving when you need to think about directions, movements, and how to design or arrange objects.