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The total surface area of a hemisphere of radius r is

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Question

The total surface area of a hemisphere of radius r is

Options

  • \[\pi r^2\]

     

  • 2 \[\pi r^2\]

     

  • 3 \[\pi r^2\]

  • 4 \[\pi r^2\]

MCQ
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Solution

The curved surface area of a hemisphere of radius is

2 \[\pi r^2\]  So, the total surface area of a hemisphere will be the sum of the curved surface area and the area of the base.

Total surface area of a hemisphere of radius r =

2 \[\pi r^2\] + \[\pi r^2\] 

=3 \[\pi r^2\]

 

 

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Chapter 21: Surface Areas and Volume of a Sphere - Exercise 21.4 [Page 25]

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R.D. Sharma Mathematics [English] Class 9
Chapter 21 Surface Areas and Volume of a Sphere
Exercise 21.4 | Q 2 | Page 25

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