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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

What is the interference of sound waves?

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प्रश्न

What is the interference of sound waves? 

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उत्तर

If two longitudinal (sound) waves arrive at a point such that compression of one wave coincides with the compression of the other wave and rarefaction coincides with the rarefaction of the other wave and then the resultant amplitude of a wave is maximum or if compression of one wave falls on the rarefaction of the other wave and vice versa and then the amplitude of the resulting wave is minimum, then these effects are interference of longitudinal (sound) waves. 

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 6: Superposition of Waves - Very Short Answer

संबंधित प्रश्‍न

A steel wire has a length of 12.0 m and a mass of 2.10 kg. What should be the tension in the wire so that speed of a transverse wave on the wire equals the speed of sound in dry air at 20 °C = 343 m s–1.


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y (x, t) = 2.0 cos 2π (10t – 0.0080x + 0.35)

Where x and y are in cm and t in s. Calculate the phase difference between oscillatory motion of two points separated by a distance of `(3λ)/4`.


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A train, standing at the outer signal of a railway station blows a whistle of frequency 400 Hz in still air. (i) What is the frequency of the whistle for a platform observer when the train (a) approaches the platform with a speed of 10 m s–1, (b) recedes from the platform with a speed of 10 m s–1? (ii) What is the speed of sound in each case? The speed of sound in still air can be taken as 340 m s–1.


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Choose the correct option:

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\[y = \left( 0 \cdot 10  \text{ mm } \right)  \sin\left[ \left( 31 \cdot 4  m^{- 1} \right)x + \left( 314  s^{- 1} \right)t \right]\]

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  3. What is the maximum displacement and the maximum speed of a portion of the string?

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For the travelling harmonic wave

y (x, t) = 2.0 cos 2π (10t – 0.0080x + 0.35)

Where x and y are in cm and t in s. Calculate the phase difference between oscillatory motion of two points separated by a distance of 4 m.


For the travelling harmonic wave

y (x, t) = 2.0 cos 2π (10t – 0.0080x + 0.35)

Where x and y are in cm and t in s. Calculate the phase difference between oscillatory motion of two points separated by a distance of `λ/2`.


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Given reasons for your answers.


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Two perfectly identical wires kept under tension are in unison. When the tension in the wire is increased by 1% then on sounding them together 3 beats are heard in 2 seconds. What is the frequency of each wire?


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