Advertisements
Advertisements
प्रश्न
The diameters of two cones are equal. If their slant heights are in the ratio 5 : 4, find the ratio of their curved surfaces.
उत्तर
Given that,
Diameters of two cones are equal
∴ Their radius are also equal i.e., `r_1=r_2`
Let the ratio of slant height be x
∴` l_1=5x and l_2=4x`
∴ Ratio of curved surface area =`C_1/C_2`
∴ `C_1/C_2=(pir_1l_1)/(pir_2l_2)=(pir_1sx)/(pir_2(4x)=)5/4`
∴ Ratio of curved surface area = 5:4
APPEARS IN
संबंधित प्रश्न
Find the volume of a right circular cone with:
height 21 cm and slant height 28 cm.
The radius and the height of a right circular cone are in the ratio 5 : 12. If its volume is 314 cubic meter, find the slant height and the radius (Use it 𝜋 = 3.14).
Find the volume of a cone whose slant height is 17 cm and radius of base is 8 cm.
A solid cone of height 8 cm and base radius 6 cm is melted and recast into identical cones, each of height 2 cm and diameter 1 cm. Find the number of cones formed.
The radii of the internal and external surfaces of a metallic spherical shell are 3 cm and 5 cm respectively. It is melted and recast into a solid right circular cone of height 32 cm. Find the diameter of the base of the cone.
From a rectangular solid of metal 42 cm by 30 cm by 20 cm, a conical cavity of diameter 14 cm and depth 24 cm is drilled out. Find :
- the surface area of remaining solid,
- the volume of remaining solid,
- the weight of the material drilled out if it weighs 7 gm per cm3.
Find the height of the cone whose base radius is 5 cm and volume is 75π cm3.
A metallic cylinder has a radius of 3 cm and a height of 5 cm. It is made of metal A. To reduce its weight, a conical hole is drilled in the cylinder, as shown and it is completely filled with a lighter metal B. The conical hole has a radius of `3/2` cm and its depth is `8/9` cm. Calculate the ratio of the volume of the metal A to the volume of metal B in the solid.
A right-angled triangle PQR where ∠Q = 90° is rotated about QR and PQ. If QR = 16 cm and PR = 20 cm, compare the curved surface areas of the right circular cones so formed by the triangle
The curved surface area of a right circular cone of height 15 cm and base diameter 16 cm is