contestada

Two speakers face each other, and they each emit a sound of wavelength . One speaker is 180 out of phase with respect to the other. If we separate the speakers by a distance 1.5, how far from the left-most speaker should we place a microphone in order to pick up the loudest sound? Ignore reflections from nearby surfaces.
A. 1/2 lambda
B. 0 lambda
C. lambda
D. 3/4 lambda
E. 1/4 lambda

Respuesta :

Answer:

C. lambda

Explanation:

Loudest sound is heard where path difference of sound wave coming from two sources will be either zero or integral multiple of wavelength . Here waves are already out of phase by 180° so at t = 0 , there is a path difference of λ /2 where λ is wavelength . So taking into account this fact , for constructive interference , path difference needed is odd multiple of λ /2

Distance between the sources = 1.5 λ .

If we place the microphone at λ , path difference between the waves coming from two sources reaching microphone = λ - 0.5λ = 0.5λ . Hence at the point constructive interference will take place .

Otras preguntas