GK Question “What Do You Understand By Smog?” general knowledge book English 2021 current affairs quiz and answers for class 7, 8, 9, 10, 12 students Exam.

What Do You Understand By Smog?

In London city above 4,000 people died t between December 4th and 9th in the year 1952. The death was caused due to exposure to smog, which is so dangerous.

In industrial cities, there are different combinations of gases that are released into the atmosphere and we call “smog”. It causes cough while breathing. The presence of particles and fumes in smog can-become absolutely poisonous. The dust is always present in the air. Tiny, solid, particles of the matter remain suspended in the air. Dust is also caused by forest fires, volcanic activity, ocean spray or soil blowing. The industrial combustion processes or the exhaust from automobiles we see ourselves.

The dust in the air, as regards its quantum is unbelievably high. In the United States alone about 45,000,000 tonnes of dust settle every year. About 72% of this is attributed to natural sources and the balance is the result of human activities.

The amount of dust naturally is greatest in big industrial cities and the fall of dust per square kilometre, each month, for a few big cities in the United States is: Detroit – 31 tonnes; Chicago – 24 tonnes, New York-30 tonnes, Los Angeles – 14 tonnes, Pittsburgh – 20 tonnes. In the cities with a large number of industrial buildings, the dust may be well even 86 tonnes per square kilometre per month.

The dust is a great health hazard. In many cities, intensive programmes are being executed to reduce this menace. Hoods are being built along with the machines which are dust-producing. Electrical devices that cause the dust to settle or blower fans, ventilation systems are also used. Water sprays and wet drilling are resorted to, in order to fight out dust. The problem of smog or the dangerous dust in the air has not been licked.