Question

Green muffler is meant for
(a) Reducing smog
(b) Sound insulation
(c) Preventing haze formation
(d) Reducing ground frost

Answer 1

Hint: Due to increasing noise around civilizations, noise pollution has become a topic of concern. A number of its major causes are vehicles, aircraft, industrial machines, loudspeakers, crackers, etc. Other appliances also contribute to noise pollution like television, transistor, radio, etc. when used at high volume.

Complete step by step answer:
Green Muffler is a technique of reducing sound pollution by planting 4-6 rows around the populated areas or noisy places like along roadsides, industrial areas, societies near highways, etc. in order that dense trees reduce sound pollution as they filter the noise and obstruct it reaching the citizens.
- They control sound pollution. Even urban noises are muffled by trees, a bit like stone walls. - A plus of using plants as noise blockers is that they absorb sounds best within the high frequencies that individuals find annoying. - Evergreen shrubs that too with broader leaves provide year-round noise protection, so they're best to plant. Trees absorb sound waves with their branches and foliage. - Plant trees with no space or less space to cut back sound pollution. - Actually soft ground is an efficient noise absorber. So, avoid hard surfaces to plant trees. Also, cultivating the bottom before planting and adding organic interest to the surface of the soil can also help to reduce noise when vegetations are going to be established. So, the right answer is ‘(b) Sound insulation’.

Note: The intensity of sound is measured in decibels (dB) . The faintest sound which may be heard by the Human ear is 1 Db. consistent with the USDA National Agroforestry Center a properly designed buffer of trees and shrubs can reduce noise by about 10 decibels or about 50% as perceived by the human ear.