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महाराष्ट्र राज्य शिक्षण मंडळएस.एस.सी (इंग्रजी माध्यम) इयत्ता ९ वी

Find the surface area and volume of sphere of the following radius. (π = 3.14 ) 9 cm

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प्रश्न

Find the surface area and volume of sphere of the following radius.  (π = 3.14 )

 9 cm

बेरीज
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उत्तर

Radius of the sphere, r = 9 cm

Surface area of the sphere = 4πr2 

= 4 × 3.14 × (9 cm)2 

= 1017.36 cm2

Volume of the sphere = `4/3`πr3

= `4/3` x 3.14 x (9 cm)3

= 3052.08 cm3

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पाठ 9: Surface Area and Volume - Practice Set 9.3 [पृष्ठ १२३]

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बालभारती Mathematics 2 [English] Standard 9 Maharashtra State Board
पाठ 9 Surface Area and Volume
Practice Set 9.3 | Q 1. (ii) | पृष्ठ १२३

संबंधित प्रश्‍न

Find the surface area of a sphere of diameter 21 cm.

`["Assume "pi=22/7]`


Find the surface area of a sphere of diameter 3.5 m.

`["Assume "pi=22/7]`


Find the total surface area of a hemisphere of radius 10 cm. [Use π = 3.14]


The diameter of the moon is approximately one-fourth of the diameter of the earth. Find the ratio of their surface area.


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]`


A right circular cylinder just encloses a sphere of radius r (see figure). Find

  1. surface area of the sphere,
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  3. ratio of the areas obtained in (i) and (ii).


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.


Two solid spheres of radii 2 cm and 4 cm are melted and recast into a cone of height 8 cm. Find the radius of the cone so formed.


A hollow sphere of internal and external radii 6 cm and 8 cm respectively is melted and recast into small cones of base radius 2 cm and height 8 cm. Find the number of cones.


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In a sphere the number of faces is 


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The ratio between the volume of a sphere and volume of a circumscribing right circular cylinder is 


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If the radius of a solid hemisphere is 5 cm, then find its curved surface area and total surface area. ( π = 3.14 )


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Find the volume of the hollow sphere whose inner diameter is 8 cm and the thickness of the material of which it is made is 1 cm . 


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A sphere cut out from a side of 7 cm cubes. Find the volume of this sphere?


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A manufacturing company prepares spherical ball bearings, each of radius 7 mm and mass 4 gm. These ball bearings are packed into boxes. Each box can have a maximum of 2156 cm3 of ball bearings. Find the:

  1. maximum number of ball bearings that each box can have.
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    (Use π = `22/7`)

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