Answer:
A) Frequency of Sound B = 242.85 Hz
B) Frequency at maximum sound intensity = 485.71 Hz
Explanation:
From intensity and path difference equations of sound waves;
the path difference for maximum intensity is x = nλ
Now, for minimum intensity, the path difference(x) is given as;
x = (2n - 1)(λ/2)
Since he has moved 0.35m,the total Path difference = (0.35) + (0.35) = 0.7 m
As n = 1,
0.7 = =(2(1) - 1)(λ/2)
So, (λ/2) = 0.7
And thus λ = 0.7 x 2 = 1.4m
From wavelength equation, we know that; λ = v/f and f = v/λ
Where v is velocity of sound
Thus ; frequency(min) = 340/1.4= 242.85 Hz
B) Now for max the path difference;
From earlier said, x = nλ
So at n=1 and λ = 0.7
x = 1 x 0.7 = 0.7
So following same equation for frequency, fmax = 340/0.7 = 485.71 Hz
