Question

1) Consider a fixed sound of intensity level SIL1 = 70 dB and another (of different frequency) whose intensity level takes on a series of values SIL2 = 50, 60, 70, 80, 90 dB. The level of the combined sound in case is: ____, ____, ____ ____, ____ in dB.

Answer 1

The expression for sound intensity can be written as,

  

  

  

Here I_o = 10^-12 W/m². For different intensities, I₁ and I₂,

Thus the total intensity is,

The total sound level is,

  

  

  

(1) When SIL₁ = 70 dB and SIL₂ = 50 dB, then

  

(2) When SIL₁ = 70 dB and SIL₂ = 60 dB, then

(3) When SIL₁ = 70 dB and SIL₂ = 70 dB, then

  

(4) When SIL₁ = 70 dB and SIL₂ = 80 dB, then

  

(5) When SIL₁ = 70 dB and SIL₂ = 90 dB, then