Engineering Board Exam Reviewer · Environmental Engineering · medium
Two machines each produce a sound level of 80 dB at a point. What is the combined sound level?
- 83 dB
- 160 dB
- 80 dB
- 86 dB
Answer
A. 83 dB
Solution
L = 10 (2 × 108) = 80 + 10 2 83 dB. Doubling identical sources adds 3 dB.
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