Ask questions and get helpful responses.


Both drawings show the same square, each of which has a side of length L = 0.86 m. An observer O is stationed at one corner of each square. Two loudspeakers are located at corners of the square, as in either drawing 1 or drawing 2. The speakers produce the same single-frequency tone in either drawing and are in phase. The speed of sound is 343 m/s. Find the single smallest frequency that will produce both constructive interference in drawing 1 and destructive interference in drawing 2.

  1. 👍
  2. 👎
  3. 👁
  4. ℹ️
  5. 🚩
  1. Fig.1: path difference Δ₁=0, since distances between each loudspeaker and point O are L
    For constructive interference Δ₁=2kλ/2=kλ (k(min)=0) => Δ₁=0.
    path difference Δ₂=L√2 – L= L(√2 –1)= 0.41L=0.353 m
    For destructive interference
    Δ₂=(2k+1)λ/2= λ/2,
    k(min)=0 => Δ₁=λ/2 =0.353 m
    => λ =2•0.353 =0.706 m
    λ=v/f => f= v/λ=
    =343/0.706 = 485.8 Hz

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩

Respond to this Question

First Name

Your Response

Still need help? You can ask a new question.