Civil Engineering - UPSC Civil Service Exam Questions - Discussion

Discussion Forum : UPSC Civil Service Exam Questions - Section 27 (Q.No. 25)
25.
Two sources generate noise levels of 90 dB and 94 dB respectively. The cumulative effect of these two noise levels on the human ear is
184 dB
95.5 dB
94 dB
92 dB
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
2 comments Page 1 of 1.

Ajay Sharma said:   3 years ago
20log{1/N[10^(N1/20)+10^(N2/20)]}
Substituting values N = no. Of sounds.
N1 = sound 1 value,
N2 = sound 2 value,
We get 92.2.
So, option D is the correct answer.

Ashish said:   6 years ago
L(eq) = 10log(10^(L1/10)+10^(L2/10)+.....).
L(eq) = 10log(10^(90/10)+10^(94/10)) = 95.5.

Post your comments here:

Your comments will be displayed after verification.