WAVE MC 1題

The equation giving the position of maximum loudness is,

d.sin(a) = m入
where a is the separation of the two loudspeakers ( = 0.8 m)
m is a +ve integer
a is angular position of the m th order max loudness
入 is the wavelength of the sound

At P, m = 1
hence, 0.8sin(a) = 入
Since for small angle of a, sin(a) = tan(a) approximately
hence, 0.8 x (1/8) = 入
i.e. 入 = 0.1 m = 10 cm