Question

The loudness, L, measured in decibels (Db), of a sound intensity, I, measured in watts per square meter, is defined as L = 10 log StartFraction I Over I 0 EndFraction, where I 0 = 10 Superscript negative 12 and is the least intense sound a human ear can hear. What is the approximate loudness of a dinner conversation with a sound intensity of 10–7?

–58 Db
–50 Db
9 Db
50 Db

Answer 1

D. 50 Db on ed

i took the test and i got it right

Answer 2

50 Db

Explanation:

we know that

The loudness in decibels is given by the formula

`L = 10log((I)/(I_0))`

where

I = sound intensity in watts per square meter (Watts/m^2)

I₀ = reference intensity, = 10^(-12) Watts/m^2

so

For I=10^(-7) Watts/m^2

substitute in the formula above and solve for L

`L = 10log((10^(-7) )/(10^(-12)))`

`L = 10log(10^(5))`

`L = 10 (5)=50\ Db`