Practical Geometry Class 8th Mathematics Term 3 Tamilnadu Board Solution

Class 8th Mathematics Term 3 Tamilnadu Board Solution

Exercise 4.1
Question 1.

Draw concentric circles for the following measurements of radii. Find out the width of each circular ring.

4 cm and 6 cm.


Answer:

4cm and 6cm
Steps of construction:

Step 1: Draw a rough image and mark the given measurement.



Step 2: Take any point O and mark its as centre.



Step 3: With O as centre, draw a circle of radius OA = 4cm.



Step 4: With O as centre, draw a circle of radius OB = 6cm.



Thus, the concentric circle C1 and C2 are drawn.


Width of the circular ring = OB – OA


= 6 – 4


= 2cm


Question 2.

Draw concentric circles for the following measurements of radii. Find out the width of each circular ring.

3.5 cm and 5.5 cm.


Answer:

3.5 cm and 5.5 cm

Steps of construction:


Step 1: Draw a rough image and mark the given measurement.



Step 2: Take any point O and mark it’s as centre.



Step 3: With O as centre, draw a circle of radius OA = 3.5 cm.



Step 4: With O as centre, draw a circle of radius OB = 5.5 cm.



Thus, the concentric circle C1 and C2 are drawn.


Width of the circular ring = OB – OA


= 5.5 – 3.5


= 2cm



Question 3.

Draw concentric circles for the following measurements of radii. Find out the width of each circular ring.

4.2 cm and 6.8 cm.


Answer:

4.2 cm and 6.8 cm

Steps of construction:


Step 1: Draw a rough image and mark the given measurement.



Step 2: Take any point O and mark it’s as centre.



Step 3: With O as centre, draw a circle of radius OA = 4.2 cm.



Step 4: With O as centre, draw a circle of radius OA = 6.8 cm.



Thus, the concentric circle C1 and C2 are drawn.


Width of the circular ring = OB – OA


= 6.8 – 4.2


= 2.6 cm



Question 4.

Draw concentric circles for the following measurements of radii. Find out the width of each circular ring.

5 cm and 6.5 cm.


Answer:

5cm and 6.5cm

Steps of construction:


Step 1: Draw a rough image and mark the given measurement.



Step 2: Take any point O and mark it’s as centre.



Step 3: With O as centre, draw a circle of radius OA = 5cm.



Step 4: With O as centre, draw a circle of radius OA = 6.5cm.



Thus, the concentric circle C1 and C2 are drawn.


Width of the circular ring = OB – OA


= 6.5 – 5


= 1.5 cm



Question 5.

Draw concentric circles for the following measurements of radii. Find out the width of each circular ring.

6.2 cm and 8.1 cm.


Answer:

6.2 cm and 8.1 cm

Steps of construction:


Step 1: Draw a rough image and mark the given measurement.



Step 2: Take any point O and mark it’s as centre.



Step 3: With O as centre, draw a circle of radius OA = 6.2cm.



Step 4: With O as centre, draw a circle of radius OA = 8.1cm.



Thus, the concentric circle C1 and C2 are drawn.


Width of the circular ring = OB – OA


= 8.1 – 6.2


= 1.9



Question 6.

Draw concentric circles for the following measurements of radii. Find out the width of each circular ring.

5.3 cm and 7 cm.


Answer:

5.3 cm and 7cm

Steps of construction:


Step 1: Draw a rough image and mark the given measurement.



Step 2: Take any point O and mark it’s as centre.



Step 3: With O as centre, draw a circle of radius OA = 5.3cm.



Step 4: With O as centre, draw a circle of radius OA = 7cm.



Thus, the concentric circle C1 and C2 are drawn.


Width of the circular ring = OB – OA


= 7 – 5.3


= 1.7 cm