The level of steady noise is measured by sound level expressed by which one of the following?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → dB
NCERT (2026-27): “Noise Pollution … The main sources of noise pollution are various factories, mechanised construction and demolition works, automobiles and aircraft, etc. There may be added periodical but polluting noise from sirens, loudspeakers used in various festivals, programmes associated with community activities. The level of steady noise is measured by sound level expressed in terms of decibels (dB).” |