Advertisements
Advertisements
प्रश्न
A hemispherical bowl made of brass has inner diameter 10.5 cm. Find the cost of tin-plating it on the inside at the rate of ₹ 16 per 100 cm2.
`["Assume "pi=22/7]`
Advertisements
उत्तर
Inner radius (r) of hemispherical bowl = `(10.5/2) cm` = 5.25 cm
Surface area of hemispherical bowl = 2πr2
= `[2xx22/7xx(5.25)^2]cm^2`
= 173.25 cm2
Cost of tin-plating 100 cm2 area = ₹ 16
Cost of tin-plating 173.25 cm2 area = `₹ (16 xx 173.25)/100`
= ₹ 27.72
Therefore, the cost of tin-plating the inner side of the hemispherical bowl is ₹ 27.72.
APPEARS IN
संबंधित प्रश्न
Find the surface area of a sphere of diameter 14 cm.
`["Assume "pi=22/7]`
Find the radius of a sphere whose surface area is 154 cm2.
`["Assume "pi=22/7]`
A hemispherical bowl is made of steel, 0.25 cm thick. The inner radius of the bowl is 5 cm. Find the outer curved surface area of the bowl.
`["Assume "pi = 22/7]`
Find the surface area of a sphere of diameter 3.5 cm.
Assuming the earth to be a sphere of radius 6370 km, how many square kilo metres is area
of the land, if three-fourth of the earth’s surface is covered by water?
The volume of a sphere is 38808 cm3; find its diameter and the surface area.
If the number of square centimeters on the surface of a sphere is equal to the number of cubic centimeters in its volume, what is the diameter of the sphere?
A hollow sphere of internal and external diameter 4 cm and 8 cm respectively is melted into a cone of base diameter 8 cm. Find the height of the cone.
A solid rectangular block of metal 49 cm by 44 cm by 18 cm is melted and formed into a solid sphere. Calculate the radius of the sphere.
The total area of a solid metallic sphere is 1256 cm2. It is melted and recast into solid right circular cones of radius 2.5 cm and height 8 cm. Calculate :
- the radius of the solid sphere.
- the number of cones recast. [Take π = 3.14]
The largest sphere is cut off from a cube of side 6 cm. The volume of the sphere will be
If the radius of a solid hemisphere is 5 cm, then find its curved surface area and total surface area. ( π = 3.14 )
Find the radius of a sphere whose surface area is equal to the area of the circle of diameter 2.8 cm
A sphere has the same curved surface area as the curved surface area of a cone of height 36 cm and base radius 15 cm . Find the radius of the sphere .
The total area of a solid metallic sphere is 1256 cm2. It is melted and recast into solid right circular cones of radius 2.5 cm and height 8 cm. Calculate: the number of cones recasted [π = 3.14]
A certain number of metallic cones, each of radius 2 cm and height 3 cm are melted and recast into a solid sphere of radius 6 cm. Find the number of cones used.
Find the volume and surface area of a sphere of diameter 21 cm.
The volume of a sphere is 905 1/7 cm3, find its diameter.
The cylinder of radius 12 cm have filled the 20 cm with water. One piece of iron drop in the stands of water goes up 6.75 cm. Find the radius of sphere piece.
The radius of a hemispherical balloon increases from 6 cm to 12 cm as air is being pumped into it. The ratios of the surface areas of the balloon in the two cases is ______.
