# Sound exits a diffraction horn loudspeaker through a rectangular opening, like a small doorway. A person is si?

Sound exits a diffraction horn loudspeaker through a rectangular opening, like a small doorway. A person is sitting at an angle theta off to the side of a diffraction horn that has a width D of 0.06 m. The speed of sound is 343 m/s. This individual does not hear a sound wave that has a frequency of 8100 Hz. When... hiển thị thêm Sound exits a diffraction horn loudspeaker through a rectangular opening, like a small doorway. A person is sitting at an angle theta off to the side of a diffraction horn that has a width D of 0.06 m. The speed of sound is 343 m/s. This individual does not hear a sound wave that has a frequency of 8100 Hz. When she is sitting at an angle theta/2, there is a different frequency that she does not hear. What is it?
I'm trying to find the answer for this one,
lamda 1= V sound/ f
from lamda, find sin θ, then find θ/2

use the new angle find lamda 2
then f2,
the right answer is f2=1.5 x10^4 Hz