Surface Areas & Volumes | Exercise 13.3 | Q1

Question 1: Diameter of the base of the cone is 10.5 cm and its slant height is 10 cm. Find its curved surface area.

Explanatory Answer | Exercise 13.3 Q1

Diameter of the cone = 10.5 cm
So, radius of the cone , r =\\frac{10.5}{2}) cm
Slant height of the cone, l = 10 cm
Curved surface area of cone = π × r × l

Take π =\\frac{22}{7})
Curved Surface Area of Cone =\\frac{22}{7}) × \\frac{10.5}{2}) × 10
= 22 x 7.5
= 165 cm²

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 ▶