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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
The engine of a train sounds a whistle at frequency v. The frequency heard by a passenger is
Answer briefly.
State the expression for apparent frequency when the source is stationary and the listener is
- moving towards the source
- moving away from the source
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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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A source and a detector move away from each other in absence of wind with a speed of 20 m/s with respect to the ground. If the detector detects a frequency of 1800 Hz of the sound coming from the source, then the original frequency of the source considering the speed of sound in air 340 m/s will be ______ Hz.
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