Viva Voce: Right Circular Cone | Lab Manuals for Class 10 PDF Download

Q.1. What is the relation between radius of base, height of cone and slant height of cone?

I² = r² + h², where l = slant height, r = radius, h = height.

Q.2. Give two examples of a right circular cone.

Birthday cap, cone of ice cream

Q.3. What is the slant height of a cone?

It is the distance of the vertex from any point on the base (circumference of circle).

Q.4. What is the volume of a cone?

1/3  πr²h, where r = radius of cone and h = height of cone.

Q.5. How many vertices are there in a right circular cone?

One

Q.6. What are different parts of a cone?

Circular base, vertex, curved surface

Q.7. If the height of a cone is equal to the radius of base of the cone, then find the slant height of the cone.

Slant height = √2 x Height of cone

Q.8. What is the curved surface area of a cone?

πrl, where r = radius of cone, l = slant height of the cone.

Q.9. If the height and slant height of a cone are 3 cm and 5 cm respectively, then the radius of its base is

4 cm

Q.10. Diameter of the base of a cone is 10.5 cm and its slant height is 10 cm. Its curved surface area is

Diameter, d = 10.5cm
Radius, r = 10.5/2 cm = 5.25 cm
Slant height, l = 10 cm
Curved surface area = πrl
= 22/7 × 5.25 × 10
= 165 cm²