19. The plane sound wave is excited by a source of oscillation frequency ν = 200 Hz. A source oscillation amplitude equal to 4 mm. Write the equation of power fluctuations ξ (0, t), if initially the bias source points as possible. Find the displacement ξ (x, t) points of the medium at a distance of x = 100 cm from the source, at the time t = 0,1 s. The speed of sound wave υ take of 300 m / s. Attenuation neglected.

Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)