рд╣рд┐рдВрджреА

Find the Total Surface Area of a Hemisphere and a Solid Hemisphere Each of Radius 10 Cm. (Use ЁЭЬЛ = 3.14)

Advertisements
Advertisements

рдкреНрд░рд╢реНрди

Find the total surface area of a hemisphere and a solid hemisphere each of radius 10 cm.
(Use ЁЭЬЛ = 3.14)

Advertisements

рдЙрддреНрддрд░

The surface area of the hemisphere =  `2πr^2` 

- `2 × 3.14 × (10)^2`

- `628 cm^2`

The surface area of solid hemisphere  =` 3πr^2`

- `3 × 3.14 × (10)^2`

-`942 cm^2`

shaalaa.com
  рдХреНрдпрд╛ рдЗрд╕ рдкреНрд░рд╢реНрди рдпрд╛ рдЙрддреНрддрд░ рдореЗрдВ рдХреЛрдИ рддреНрд░реБрдЯрд┐ рд╣реИ?
рдЕрдзреНрдпрд╛рдп 21: Surface Areas and Volume of a Sphere - Exercise 21.1 [рдкреГрд╖реНрда рео]

APPEARS IN

рдЖрд░.рдбреА. рд╢рд░реНрдорд╛ Mathematics [English] Class 9
рдЕрдзреНрдпрд╛рдп 21 Surface Areas and Volume of a Sphere
Exercise 21.1 | Q 3 | рдкреГрд╖реНрда рео

рд╡реАрдбрд┐рдпреЛ рдЯреНрдпреВрдЯреЛрд░рд┐рдпрд▓VIEW ALL [2]

рд╕рдВрдмрдВрдзрд┐рдд рдкреНрд░рд╢реНрди

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 14 cm.


The surface area of a sphere is 5544 `cm^2`, find its diameter.


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 Rs. 4 per 100 `cm^2`


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`


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


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

 

The hollow sphere, in which the circus motor cyclist performs his stunts, has a diameter of 7 m. Find the area available to the motorcyclist for riding.


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 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 


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

3.5 cm


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


Find the length of the wire of diameter 4 m that can be drawn from a solid sphere of radius 9 m. 


The given figure shows the cross-section of a cone, a cylinder and a hemisphere all with the same diameter 10 cm and the other dimensions are as shown.


Calculate :

  1. the total surface area.
  2. the total volume of the solid and
  3. the density of the material if its total weight is 1.7 kg.

The radius of two spheres are in the ratio of 1 : 3. Find the ratio between their volume.


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

Englishрд╣рд┐рдВрджреАрдорд░рд╛рдареА


      Forgot password?
Use app×