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In Discussing Doppler Effect, We Use the Word "Apparent Frequency". Does It Mean that the Frequency of the Sound is Still that of the Source and It is Some Physiological Phenomenon - Physics

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प्रश्न

In discussing Doppler effect, we use the word "apparent frequency". Does it mean that the frequency of the sound is still that of the source and it is some physiological phenomenon in the listener's ear that gives rise to Doppler effect? Think for the observer approaching the source and for the source approaching the observer.

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उत्तर

The frequency of the sound is still that of the source. However, the frequency of the vibrations received by the observer changes due to relative motion.
If both (the observer and the source) move towards each other, then the frequency of the vibrations received by the observer will be higher compared to the original frequency.

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Doppler Effect
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अध्याय 16: Sound Waves - Short Answers [पृष्ठ ३५१]

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एचसी वर्मा Concepts of Physics Vol. 1 [English] Class 11 and 12
अध्याय 16 Sound Waves
Short Answers | Q 8 | पृष्ठ ३५१

संबंधित प्रश्न

A narrow sound pulse (for example, a short pip by a whistle) is sent across a medium. (a) Does the pulse have a definite (i) frequency, (ii) wavelength, (iii) speed of propagation? (b) If the pulse rate is 1 after every 20 s, (that is the whistle is blown for a split of second after every 20 s), is the frequency of the note produced by the whistle equal to 1/20 or 0.05 Hz


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The change in frequency due to Doppler effect does not depend on


Answer briefly.

What is Doppler effect?


Answer briefly.

State the expression for apparent frequency when the source is stationary and the listener is

  1. moving towards the source
  2. moving away from the source

Answer briefly.

State the expression for apparent frequency when source of sound and listener are

  1. moving towards each other
  2. moving away from each other

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Observer in motion and Source at rest.

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Discuss the following case-

Both are in motion

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  2. Source and Observer resides from each other
  3. Source chases Observer
  4. Observer chases Source

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  1. the frequency of sound as heard by an observer standing on the platform is 400 Hz.
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  3. the frequency of sound as heard by the observer standing on the platform will increase.
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