Question

Question Details:
A row of seats is parallel to a stage at a distance of 8.70 m from it. At the center and front of the stage is a diffraction horn loudspeaker that has a width of 7.50 cm. The speaker is playing a tone at a frequency of 9300 Hz . The speed of sound is 344 m/s.

What is the separation between two seats, located on opposite sides of the center of the row, at which the tone cannot be heard?

I divided 344 by 9300 and got 0.03699

and then i drew a triangle and divided 7.50 by 3.6989 which gave me 2.02 i then use the pygathorean theorem, and got the additional side as 6.52 which divided 3.6989, and then i used that value to multiply vy 8.70m to get the distance from the centre.

I am stuck can someone please help. I keep getting the wrong answer but I don't understand why.

Answer 1

Minimum intensity occurs at an angle θmin given by dsinθmin = λ
d is the slit width (0.075m)
Stadnik's class?

Answer 2

yeah i did that but the answer is incorrect