Home
Class 9
MATHS
Find the surface area and total surface ...

Find the surface area and total surface area of a hemisphere of radius 21cm.

Text Solution

Verified by Experts

Given : radius, `r = 21cm`
C.S.A of a hemisphere = `2pir^2`
C.S.A of a hemisphere = `2xx22/7xx7xx7`=`2772 cm^2`
T.S.A of a hemisphere = `3pir^2`
T.S.A of a hemisphere = `3xx22/7xx7xx7` = `4158 cm^2`
Hence, Curved and total surface areas are `2772 cm^2` and `4158 cm^2`.
Promotional Banner

Topper's Solved these Questions

  • SURFACE AREA AND VOLUME OF A RIGHT CIRCULAR CYLINDER CONE

    RD SHARMA|Exercise All Questions|128 Videos

  • TABULAR REPRESENTATION OF STATISTICAL DATA

    RD SHARMA|Exercise All Questions|62 Videos

Similar Questions

Explore conceptually related problems

Find the total surface area of a hemisphere of radius 10cm

Find (i) the curved surface area and (ii) the total surface area of a hemisphere of radius 21cm.

The total surface area of a hemisphere of radius 7 cm is

Find the volume,curved surface area and the total surface area of a hemisphere of radius 10.5cm.

Find total surface area of a solid hemi-sphere of radius 7cm.

Find the volume , curved surface area and the total surface area of a hemisphere of radius 7 cm .

The surface area of a sphere of radius 21 cm is

Find the total surface area of a hemisphere whose radius is 1 cm.

The total surface area of a solid hemisphere of radius r is

Find the volume and the total surface area of a hemisphere of radius 3.5 cm. (U s e\ pi=(22)/7)

RD SHARMA-SURFACE AREA AND VOLUME OF A SPHERE -All Questions
  1. A spherical ball of lead 3cm in diameter is melted and recast into ...

    Text Solution

    |

  2. Find the surface area of a sphere of radius 7cm.

    Text Solution

    |

  3. Find the surface area and total surface area of a hemisphere of rad...

    Text Solution

    |

  4. The radius of a spherical balloon increases from 7cm to 14cm as air is...

    Text Solution

    |

  5. A sphere, a cylinder and a cone are of the same radius and same hei...

    Text Solution

    |

  6. Show that the surface area of a sphere is the same as that of the l...

    Text Solution

    |

  7. A right circular cylinder just encloses a sphere of radius r as sho...

    Text Solution

    |

  8. A hemispherical bowl is made of steel, 0.25 cm thick. The inner rad...

    Text Solution

    |

  9. The internal and external diameters of a hollow hemispherical vesse...

    Text Solution

    |

  10. The internal and external diameters of a hollow hemispherical vesse...

    Text Solution

    |

  11. A storage tank consists of a circular cylinder with a hemisphere ad...

    Text Solution

    |

  12. A toy is in the shape of a right circular cylinder with a hemispher...

    Text Solution

    |

  13. A wooden toy is in the form of a cone surmounted on a hemisphere. T...

    Text Solution

    |

  14. The diameter of a sphere is decreased by 25%. By what per cent does...

    Text Solution

    |

  15. Find the surface area of a sphere of radius: 10.5 cm         (ii...

    Text Solution

    |

  16. Find the surface area of a sphere of diameter: (i) 14 cm (ii) 21 cm (i...

    Text Solution

    |

  17. Find the total surface area of a hemisphere of radius 10 cm

    Text Solution

    |

  18. The surface area of a sphere is 5544\ c m^2, find its diameter.

    Text Solution

    |

  19. A hemispherical bowl made of brass has inner diameter 10.5cm. Find ...

    Text Solution

    |

  20. The dome of a building is in the form of a hemisphere. Its radius i...

    Text Solution

    |