Question
Biology Question on Environmental Issues
What is the intensity of sound in normal conversation?
A
10-20 dB
B
30-60 dB
C
70-90 dB
D
120-150dB.
Answer
30-60 dB
Explanation
Solution
Unit of sound level is decibel. As referrence intensity, sound of noise level is taken as 00 dB. 10 dB is ten times the threshold intensity, 20 dB 100 times, 40 dB is 104, 100dB is 10 times the threshold intensity. Moderate conversation produces 60 dB sound. Unwanted sound is noise and is therefore pollutant.