Answer
given,
Distance for decibel reading
r₁ = 13 m
r₂ = 24 m
When the engineer is at r₁ reading is β₁ = 101 dB
now, Calculating the Intensity at r₁
Using formula
[tex]\beta = 10 log(\dfrac{I}{I_0})[/tex]
I₀ = 10⁻¹² W/m²
now inserting the given values
[tex]101= 10 log(\dfrac{I}{10^{-12}})[/tex]
[tex]10.1= log(\dfrac{I}{10^{-12}})[/tex]
[tex]\dfrac{I}{10^{-12}}= 10^{10.1}[/tex]
[tex]I =10^{10.1} \times 10^{-12}[/tex]
I = 0.01258 W/m²
now, calculating power at r₁
P₁ = I₁ A₁
P₁ = 0.01258 x 4 π r²
P₁ = 0.01258 x 4 π x 13²
P₁ = 26.72 W