हिंदी

Find the surface area and volume of sphere of the following radius. (π = 3.14 ) 3.5 cm - Geometry

Advertisements
Advertisements

प्रश्न

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

3.5 cm

योग
Advertisements

उत्तर

Radius of the sphere, r = 3.5 cm

Surface area of the sphere =  4 πr2 

= 4 × 3.14 × (3.5)2 

= 153.86 cm2

Volume of the sphere = `4/3`πr3 

= `4/3 xx 3.14 xx (3.5)^3`

= 179.50 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. (iii) | पृष्ठ १२३

संबंधित प्रश्न

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

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


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

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


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

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

 


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

  1. surface area of the sphere,
  2. curved surface area of the cylinder,
  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.


The surface area of a solid metallic sphere is 2464 cm2. It is melted and recast into solid right circular cones of radius 3.5 cm and height 7 cm. Calculate:

  1. the radius of the sphere.
  2. the number of cones recast. (Take π = `22/7`)

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.


Find the surface area of a sphere of diameter 3.5 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 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?


The volume of one sphere is 27 times that of another sphere. Calculate the ratio of their :

  1. radii,
  2. surface areas. 

Metallic spheres of radii 6 cm, 8 cm and 10 cm respectively are melted and recasted into a single solid sphere. Taking π = 3.1, find the surface area of the solid sphere formed.


The surface area of a solid sphere is increased by 12% without changing its shape. Find the percentage increase in its:

  1. radius
  2. volume

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. 


Total volume of three identical cones is the same as that of a bigger cone whose height is 9 cm and diameter 40 cm. Find the radius of the base of each smaller cone, if height of each is 108 cm. 


Spherical marbles of diameter 1.4 cm are dropped into beaker containing some water and are fully submerged. The diameter of the beaker is 7 cm. Find how many marbles have been dropped in it if the water rises by 5.6 cm.


The cross-section of a tunnel is a square of side 7 m surmounted by a semi-circle as shown in the adjoining figure. The tunnel is 80 m long.

Calculate:

  1. its volume,
  2. the surface area of the tunnel (excluding the floor) and
  3. its floor area.   


If a hollow sphere of internal and external diameters 4 cm and 8 cm respectively melted into a cone of base diameter 8 cm, then find the height of the cone.


If a sphere is inscribed in a cube, find the ratio of the volume of cube to the volume of the sphere.


The total surface area of a hemisphere of radius r is


A sphere and a cube are of the same height. The ratio of their volumes 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 cone and a hemisphere have equal bases and equal volumes the ratio of their heights is


The model of a building is constructed with the scale factor 1 : 30. 
(i) If the height of the model is 80 cm, find the actual height of the building in meters.
(ii) If the actual volume of a tank at the top of the building is 27m3, find the volume of the tank on the top of the model. 


If the surface area of a sphere is 2826 cmthen find its volume. ( π= 3.14)


Find the surface area of a sphere, if its volume is 38808 cubic cm. `(π = 22/7)`


A solid metallic cylinder has a radius of 2 cm and is 45 cm tall. Find the number of metallic spheres of diameter 6 cm that can be made by recasting this cylinder . 


A hemispherical bowl of internal radius 9 cm is full of liquid. This liquid is to be filled into conical shaped small containers each of diameter 3 cm and height 4 cm.  How many containers are necessary to empty the bowl?


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 volume of remaining solid 


A solid, consisting of a right circular cone standing on a hemisphere, is placed upright, in a right circular cylinder, full of water and touches the bottom. Find the volume of water left in the cylinder, having given that the radius of the cylinder is 3 cm and its height is 6 cm; the radius of the hemisphere is 2 cm and the height of the cone is 4 cm. Give your answer to the nearest cubic centimetre.


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. 


The volume of a sphere is 905 1/7 cm3, find its 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 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.


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.
  2. mass of each box of ball bearings in kg.
    (Use π = `22/7`)

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×