Advertisements
Advertisements
प्रश्न
Find the curved surface area of a right circular cone whose height is 15 cm and base radius is 8 cm. tan β = `3/4`.
उत्तर
Given, height of cone, h = 15 cm
Base radius of cone, r = 8 cm
∴ Slant height of cone, l = `sqrt(h^2 + r^2)`
= `sqrt((15)^2 + (8)^2)`
= `sqrt(225 + 64)`
= `sqrt(289)`
= 17 cm
Now, curved surface area of cone = πrl
= `22/8 xx 8 xx 17`
= `2992/7`
= 427.429 cm2
APPEARS IN
संबंधित प्रश्न
A solid right circular cone of height 120 cm and radius 60 cm is placed in a right circular cylinder full of water of height 180 cm such that it touches the bottom . Find the volume of water left in the cylinder , if the radius of the cylinder is equal to the radius of te cone
A heap of rice in the form of a cone of diameter 9 m and height 3.5 m. Find the volume of rice. How much canvas cloth is required to cover the heap ?
A circus tent is cylindrical to a height of 3 metres and conical above it. If its diameter is 105 m and the slant height of the conical portion is 53 m, calculate the length of the canvas 5 m wide to make the required tent.
The radii of the base of a cylinder and a cone are in the ratio 3 : 4 and their heights are in the ratio 2 : 3. What is the ratio of their volumes?
A metallic bucket, open at the top, of height 24 cm is in the form of the frustum of a cone, the radii of whose lower and upper circular ends are 7 cm and 14 cm, respectively. Find
- the volume of water which can completely fill the bucket;
- the area of the metal sheet used to make the bucket.
The circular ends of a bucket are of radii 35 cm and 14 cm and the height of the bucket is 40 cm. Its volume is
The frustum shaped outer portion of the table lamp has to be painted including the top part. Find the total cost of painting the lamp if the cost of painting 1 sq.cm is ₹ 2.
The number of conical bottles of radius 2 cm and height 3.6 cm, required to empty the liquid from a cylindrical bottle of radius 6 cm and height 10 cm is ______.
The base radii of two circular cones of the same height are in the ratio 3 : 5. The ratio of their volumes are ______.
A bucket is in the form of a frustum of a cone and holds 28.490 litres of water. The radii of the top and bottom are 28 cm and 21 cm, respectively. Find the height of the bucket.