Ques. 1AIPMT 2001
What is the intensity of sound in normal conversation?
- 30–60 dB
- 10–20 dB
- 120–150 dB
- 70–90 dB
Answer
(1) 30–60 dB
Solution
Sound intensity is measured in decibels (dB). Rustling of leaves or a whisper is about 10–20 dB, normal conversation about 30–60 dB and heavy traffic about 70–90 dB.
As per NCERT, a jet plane or rocket taking off produces noise of 150 dB or more, and prolonged exposure to such high levels damages hearing.
∴ Normal conversation lies in the range 30–60 dB.
Answer: (1)
Out of syllabus