Advertisements
Advertisements
प्रश्न
A joker’s cap is in the form of right circular cone of base radius 7 cm and height 24 cm. Find the area of the sheet required to make 10 such caps.
`["Assume "pi=22/7]`
उत्तर
Radius (r) of conical cap = 7 cm
Height (h) of conical cap = 24 cm
Slant height (l) of conical cap = `sqrt(r^2+h^2)`
= `[sqrt((7)^2+(24)^2)] cm`
= `sqrt (576 + 49) cm`
= `sqrt625 cm`
= 25 cm
Curved surface area of 1 conical cap = πrl
= `(22/7xx7xx25)cm^2`
= 550 cm2
Curved surface area of 10 such conical caps = (10 × 550) cm2 = 5500 cm2
Therefore, the required area of the sheet is 5500 cm2.
APPEARS IN
संबंधित प्रश्न
Find the curved surface area of a cone, if its slant height is 60 cm and the radius of its base is 21 cm.
The radius of a cone is 5 cm and vertical height is 12 cm. Find the area of the curved surface.
Find the volume of a right circular cone with:
radius 6 cm, height 7 cm.
The ratio of volumes of two cones is 4 : 5 and the ratio of the radii of their bases is 2:3. Find the ratio of their vertical heights.
The volume of a right circular cone is 9856 cm3. If the diameter of the base is 28 cm, find:
(i) height of the cone (ii) slant height of the cone (iii) curved surface area of the cone.
The curved surface area of a cone is 12320 cm2. If the radius of its base is 56 cm, find its height.
The area of the base of a conical solid is 38.5 cm2 and its volume is 154 cm3. Find the curved surface area of the solid.
Volume of a cone is 1232 cm3 and its height is 24 cm. Find the surface area of the cone. `( π = 22/7)`
A sphere and a cone have the same radii. If their volumes are also equal, prove that the height of the cone is twice its radius.
A buoy is made in the form of a hemisphere surmounted by a right circular cone whose circular base coincides with the plane surface of the hemisphere. The radius of the base of the cone is 3.5 m and its volume is two-third the volume of hemisphere. Calculate the height of the cone and the surface area of the buoy, correct to two decimal places.