हिंदी

Find the surface area and volume of sphere of the following radius. (π = 3.14) 4 cm

Advertisements
Advertisements

प्रश्न

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

4 cm

योग
Advertisements

उत्तर

Radius of the sphere, r = 4 cm

Surface area of the sphere = 4πr2 

= 4 × 3.14 × (4)2 

= 200.96 cm2

Volume of the sphere = `4/3`πr3

= `4/3 xx 3.14 xx (4)^3`

= 267.95 cm3

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 9: Surface Area and Volume - Practice Set 9.3 [पृष्ठ १२३]

APPEARS IN

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

संबंधित प्रश्न

Find the surface area of a sphere of radius 10.5 cm.

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


Find the surface area of a sphere of radius 14 cm.

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


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

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


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]`


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 model of a ship is made to a scale 1: 300

1) The length of the model of the ship is 2 m. Calculate the lengths of the ship.

2) The area of the deck ship is 180,000 m2. Calculate the area of the deck of the model.

3) The volume of the model in 6.5 m3. Calculate the volume of the ship.


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.


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


The dome of a building is in the form of a hemisphere. Its radius is 63 dm. Find the cost of painting it at the rate of Rs. 2 per sq. m. 


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 hemi-spherical dome of a building needs to be painted. If the circumference of the base of
the dome is 17.6 cm, find the cost of painting it, given the cost of painting is Rs. 5 per l00
`cm^2`


How many balls each of radius 1 cm can be made by melting a bigger ball whose diameter is 8 cm?


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 solid sphere of radius 15 cm is melted and recast into solid right circular cones of radius 2.5 cm and height 8 cm. Calculate the number of cones recast. 


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.


A hemi-spherical bowl has negligible thickness and the length of its circumference is 198 cm. Find the capacity of the bowl. 


What is the least number of solid metallic spheres, each of 6 cm diameter, that should be melted and recast to form a solid metal cone whose height is 45 cm and diameter 12 cm?


A solid is in the form of a cone standing on a hemi-sphere with both their radii being equal to 8 cm and the height of cone is equal to its radius. Find, in terms of π, the volume of the solid. 


Find the radius of a sphere whose surface area is 154 cm2.

 

Mark the correct alternative in each of the following:
In a sphere the number of faces is 


The total surface area of a hemisphere of radius r is


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


A sphere is placed inside a right circular cylinder so as to touch the top, base and lateral surface of the cylinder. If the radius of the sphere is r, then the volume of the cylinder is 


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

 9 cm


Find the radius of the sphere whose surface area is equal to its volume .


How many lead balls of radii 1 cm each can be made from a sphere of 8 cm radius?


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 . 


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 weight of the material drilled out if it weighs 7 gm per cm3.


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.


A conical tent is to accommodate 77 persons. Each person must have 16 m3 of air to breathe. Given the radius of the tent as 7 m, find the height of the tent and also its curved surface area. 


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


How many spherical bullets can be made out of a solid cube of lead whose edge measures 44 cm, each bullet being 4 cm in diameter?


A vessel is in he form of an inverted cone. Its height is 11 cm., and the radius of its top which is open is 2.5 cm. It is filled with water up to the rim. When lead shots, each of which is a sphere of radius 0.25 cm., are dropped 2 into the vessel, `2/5`th of the water flows out. Find the number of lead shots dropped into the vessel.


The radius of a sphere is 10 cm. If we increase the radius 5% then how many % will increase in volume?


The radius of a sphere increases by 25%. Find the percentage increase in its surface area


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 ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×