What is the intensity level in deibels of a sound that has a

What is the intensity level in deibels of a sound that has an intensity of 2.1E-4 W/m²?

Solution

The Sound Intensity Level can be expressed as :

L_I = 10 log₁₀ (I_s / I_ref)                                                               { eq.1 }

where, L_I = sound intensity level (dB) = ?

I = sound intensity (W/m²) = 2.1 x 10^-4 W/m²

I_ref = reference sound intensity = 10^-12 W/m²

inserting the values in above eq.

L_I = 10 log₁₀ [( 2.1 x 10^-4 W/m²) / (10^-12 W/m²)]   dB

L_I = 10 log₁₀ (2.1 x 10⁸) dB

L_I = 83.2 dB