Environmental Issues · Question 83

What is the intensity of sound in normal conversation?

1. 30–60 dB
2. 10–20 dB
3. 120–150 dB
4. 70–90 dB

Answer

(1) 30–60 dB

Solution

Sound intensity is measured in decibels (dB).

⇒ Rustling of leaves / whisper ≈ 10–20 dB; normal conversation ≈ 30–60 dB; heavy traffic ≈ 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)