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प्रश्न
Explain Reflection at curved surfaces.
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उत्तर
- When the sound waves are reflected from the curved surfaces, the intensity of the reflected waves is changed.
- When reflected from a convex surface, the reflected waves are diverged out and the intensity is decreased.
- When sound is reflected from a concave surface, the reflected waves are converged and focused at a point. So the intensity of reflected waves is concentrated at a point.
- Parabolic surfaces are used when it is required to focus the sound at a particular point. Hence, many halls are designed with parabolic reflecting surfaces.
- In elliptical surfaces, sound from one focus will always be reflected the other focus, no matter where it strikes the wall.
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