question_answer 58)

  Establish the relationship between speed of sound, its wavelength and frequency. If velocity of sound in air is 340 . Calculate (i) wavelength when frequency is 256 Hz. (ii) frequency when wavelength is 0.85 m.  

Answer:

  The speed of sound is defined as the distance which a point on a wave, such as a compression or a rarefaction, travels per unit time. We know that,                             Here,  is the wavelength of the sound wave. It is the distance travelled by the sound wave in one time period (T) of the wave We know that,(where v = frequency)                                 i.e.,              Speed = wavelength x frequency Given, speed of sound in air v = 340 m/s and frequency v = 256 Hz. (i)                 Speed = wavelength x frequency (ii) Again, given wavelength Then. frequency of sound in air. (speed = wavelength x frequency) Thus, frequency of sound is 400 Hz.