The speed of sound in air is 340 ms–1. If its frequency is 170 Hz, then the distance between compression and immediate rarefaction (in metres) is

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Key Points

  • Compression: A region in a longitudinal wave where the particles are closest together. This occurs due to the pressure increase caused by the wave.
  • Rarefaction: A region in a longitudinal wave where the particles are furthest apart. This occurs due to the pressure decrease caused by the wave.
  • Wavelength (λ): The distance between two consecutive compressions or rarefactions in a sound wave. It is measured in metres (m).
  • Speed of Sound: The speed at which sound waves travel through a medium. In air, this is approximately 340 m/s under standard conditions.
  • Frequency (f): The number of oscillations or waves produced per second, measured in Hertz (Hz).
  • The speed of sound in air (v) is 340 m/s, which is a standard value for air under normal conditions.
  • The frequency (f) of the sound wave is given as 170 Hz.
  • The wavelength (λ) of the sound wave can be calculated using the relation: λ = v/f.
  • The distance between a compression and the immediate rarefaction is half of the wavelength (λ/2).
  • Formula Relation: The speed of sound is related to wavelength and frequency by the formula: v = f * λ, where:
    • v = speed of sound
    • f = frequency
    • λ = wavelength.
  • To calculate the wavelength (λ): Using the formula λ = v/f:
    • Speed of sound (v) = 340 m/s
    • Frequency (f) = 170 Hz
    • λ = v/f = 340/170 = 2 m
  • To calculate the distance between compression and rarefaction: This distance is λ/2:
    • λ/2 = 2/2 = 1 m
  • Thus, the distance between the compression and the immediate rarefaction is 1 metre.
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