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
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]`
On a map drawn to a scale of 1: 50,000, a rectangular plot of land ABCD has the following dimensions. AB = 6 cm; BC = 8 cm and all angles are right angles. Find:
1) the actual length of the diagonal distance AC of the plot in km.
2) the actual area of the plot in sq. km.
A solid cone of radius 5 cm and height 8 cm is melted and made into small spheres of radius 0.5 cm. Find the number of spheres formed.
Find the surface area of a sphere of radius 10.5 cm.
Find the surface area of a sphere of diameter 3.5 cm.
A cylinder of same height and radius is placed on the top of a hemisphere. Find the curved
surface area of the shape if the length of the shape be 7 cm.
A wooden toy is in the form of a cone surmounted on a hemisphere. The diameter of the base
of the cone is 16 cm and its height is 15 cm. Find the cost of painting the toy at Rs. 7 per 100
`cm^2`.
The diameter of the moon is approximately one fourth of the diameter of the earth. Find the
ratio of their surface areas.
Eight metallic spheres; each of radius 2 mm, are melted and cast into a single sphere. Calculate the radius of the new sphere.
If the surface area of a sphere is 144π m2, then its volume (in m3) is
If a solid sphere of radius 10 cm is moulded into 8 spherical solid balls of equal radius, then the surface area of each ball (in sq.cm) is
Find the surface area and volume of sphere of the following radius. (π = 3.14 )
9 cm
Find the length of the wire of diameter 4 m that can be drawn from a solid sphere of radius 9 m.
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 volume of a sphere is 905 1/7 cm3, find its diameter.
The radius of two spheres are in the ratio of 1 : 3. Find the ratio between their volume.
The surface area of a solid metallic sphere is 616 cm2. It is melted and recast into smaller spheres of diameter 3.5 cm. How many such spheres can be obtained?
The internal and external diameters of a hollow hemispherical vessel are 20 cm and 28 cm respectively. Find the cost to paint the vessel all over at ₹ 0.14 per cm2
The total surface area of a hemisphere is how many times the square of its radius
