Curved Surface Area of Cylinder | Exer 13.2 Q8

Question 8: In a hot water heating system, there is a cylindrical pipe of length 28 m and diameter 5 cm. Find the total radiating surface in the system.

Explanatory Answer

The radiating surface is the curved surface area of the cylindrical pipe.

The length of the pipe = height of the cylinder = 28 m
Diameter of the pipe = 5 cm
So, radius = 2.5 cm = \\frac{2.5}{100}) m = \\frac{1}{40}) m

Curved surface area of the cylindrical pipe = 2πrh
Take π = \\frac{22}{7})

Radiating surface = curved surface area of cylinder = 2 × \\frac{22}{7}) × \\frac{1}{40}) × 28
  \\frac{44}{10}) = 4.4 m²
So, total radiating surface in the heating system = 4.4 m²

Exercise 13.1 | Surface Area of Cubes & Cuboids

1. Class 9 Exercise 13.1 Question 3 | Height of hall ▶
2. Class 9 Exercise 13.1 Question 6 | TSA of Herbarium ▶
3. Class 9 Exercise 13.1 Question 7 | Shanti Sweets ▶

Exercise 13.2 | Surface Area of Cylinders

1. Class 9 Exercise 13.2 Question 3 | CSA TSA of Metal Pipe ▶
2. Class 9 Exercise 13.2 Question 4 | Roller & Playground ▶
3. Class 9 Exercise 13.2 Question 9 | Cylindrical Petrol Tank ▶
4. Class 9 Exercise 13.2 Question 10 | CSA of Decorative Lampshade ▶

Exercise 13.3 | Surface Area of Cones

1. Class 9 Exercise 13.3 Question 5 | Length of Tarpaulin 3 m wide ▶
2. Class 9 Exercise 13.3 Question 8 | Cost of painting conical barricades ▶

Exercise 13.4 | Surface Area of Spheres & Hemispheres

1. Class 9 Exercise 13.4 Question 8 | Outer CSA of hemispherical bowl ▶
2. Class 9 Exercise 13.4 Question 9 | Surface area of sphere & Cylinder ▶