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Two identical solid hemispheres of equal base radius r cm are stuck together along their bases. The total surface area of the combination is 6πr2. - Mathematics

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Question

Two identical solid hemispheres of equal base radius r cm are stuck together along their bases. The total surface area of the combination is 6πr2.

Options

  • True

  • False

MCQ
True or False
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Solution

This statement is False.

Explanation:

Curved surface area of a hemisphere = 2πr2

Here, two identical solid hemispheres of equal radius are stuck together.

So, base of both hemispheres is common.

∴ Total surface area of the combination

= 2πr2 + 2πr2 

= 4πr2

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Chapter 12: Surface Areas and Volumes - Exercise 12.2 [Page 142]

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NCERT Exemplar Mathematics [English] Class 10
Chapter 12 Surface Areas and Volumes
Exercise 12.2 | Q 1 | Page 142

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