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प्रश्न
How do animals sense impending danger of hurricane?
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उत्तर
Hurricane produces a shock wave which has a speed greater than the speed of sound. It travels with a supersonic sound that can be easily sensed by animals using the Doppler effect. The multiple reflections of sound can be easily sensed by animals.
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संबंधित प्रश्न
State the expression for apparent frequency when listener is stationary and source is moving towards the listener.
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The difference between the apparent frequency of a source of sound as perceived by the observer during its approach and recession is 2% of the frequency of the source. If the speed of sound in air is 300 ms-1, then the velocity of the source is ______.
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With what velocity an observer should move relative to a stationary source so that a sound of double the frequency of source is heard by an observer?
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