RBSE Solutions Class 6 Maths Chapter 8 Basic Geometrical Concepts and Shapes Exercise 8.1

Question 1. Write the name of the line segments shown in the diagrams below.
Answer:
(i) XY
(ii) AB, BC
(iii) PQ, QR, RS
(iv) UV, VW, WX, XY, YZ
In simple words: Look at each drawing and identify all the straight parts that connect two points. These straight parts are called line segments.

🎯 Exam Tip: A line segment has a definite start and end point. Always name it using the letters at its two endpoints, such as AB or XY.

Question 2. Draw line segments by using scale.
(i) 4.0 cm
(ii) 3.7 cm
(iii) 7.5 cm
(iv) 5.1 cm
Answer:
(i) 4.0 cm
(ii) 3.7 cm
(iii) 7.5 cm
(iv) 5.1 cm
In simple words: To draw these lines, use a ruler to measure the exact length needed. Start at the zero mark on the ruler and draw a straight line until you reach the correct measurement, marking clear start and end points.

🎯 Exam Tip: Always place your ruler carefully on the paper and start drawing from the zero mark for accurate measurement. Double-check your drawn length after lifting the ruler.

Question 3. Draw a line of the length of your pen. Write the right length of the pen.
Answer:
The length of a standard pen is usually about 12 cm. Students should measure their own pen to get its exact length.
In simple words: Use a ruler to find out how long your pen is. Then, draw a straight line on your paper that is exactly the same length as your pen.

🎯 Exam Tip: Pen lengths can vary slightly. Make sure to actually measure your specific pen and record its length accurately.

Question 4. Draw a line of 3.2 cm using scale. Draw another line of the double length of it.
Answer:
First, draw a line segment of 3.2 cm.
Next, calculate the double length of 3.2 cm, which is \( 3.2 \times 2 = 6.4 \) cm. Then draw a new line segment of 6.4 cm.
In simple words: First, draw a line that is 3.2 cm long using your ruler. Then, draw another line that is twice as long, which means it will be 6.4 cm long.

🎯 Exam Tip: Always calculate the double length first and clearly label both lines with their respective measurements.

Question 5. Draw any line AB and again draw a line of equal length without measuring it. (Hint - Use divider)
Answer:
To draw a line segment of equal length without measuring, use a compass or divider.
**Step 1:** Draw any line segment, for example, AB.
**Step 2:** Open a compass or divider to the exact length of line segment AB. Place the pointed end on point A and the pencil end on point B.
**Step 3:** Now, draw a new ray (a line starting at a point and extending infinitely in one direction), for example, starting at point C. Without changing the compass opening, place the pointed end of the compass at point C and draw an arc to mark a new point D on the ray.
**Step 4:** The line segment CD will be exactly the same length as AB. This method ensures accurate copying of length without using a ruler to measure.
In simple words: First, draw any line segment, like AB. Then, use a compass or divider to pick up the exact length of AB. After that, draw a new line and use the compass to mark off the same length on this new line, making a segment CD that is exactly as long as AB.

🎯 Exam Tip: The key to using a divider is to keep its opening fixed. This ensures the transferred length is identical to the original segment.

Question 6. Measure the lines below using divider on scale and write its measurement.
Answer:
(i) 2.8 cm
(ii) 2 cm
(iii) 4 cm
(iv) 4.5 cm
Using a divider allows for accurate transfer of lengths from a diagram to a ruler for precise measurement.
In simple words: To find the length of each line, use a divider to match its length, then place the divider against a ruler to read the measurement. Write down each length you find.

🎯 Exam Tip: When using a divider, make sure the points are exactly at the ends of the line segment to get the most accurate measurement.