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प्रश्न
What is a megaphone ? Name the principle on which a megaphone works.
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उत्तर
A megaphone is a large cone-shaped device used for amplifying and directing the voice of a person who speaks into it. A megaphone works on the principle of multiple reflections of sound. It is used for addressing a small gathering of people.
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संबंधित प्रश्न
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