Question

If a large housefly 2.4 m away from you makes a noise of 47.0 dB, what is the noise level (in dB) of 5400 flies at that distance, assuming interference has a negligible effect?

Answer 1

Answer:

the noise level of 5400 flies is equal to 84.32 dB

Explanation:

Noise made by house flies = 47 dB from the distance of 2.4 m

to calculate the noise of 5400 flies at a distance of 2.4 m.

the intensity of noise

  $10 log_{10}(\dfrac{I}{I_0}) = 47 dB$

now,  I' = 5400 I₀

=     $10 log_{10}(\dfrac{5400 I}{I_0})$

=    $10 [log_{10}[5400] +log_{10}(\dfrac{I}{I_0}))$      

= 10 ( 3.732 + 4.7 )                            

= 84.32 dB                                          

hence, the noise level of 5400 flies is equal to 84.32 dB