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CBSE Gujarat Board Haryana Board

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Class 10 Class 12

Which one of the flowing is the correct percentage of the two (out of the total of 4 ) green-house gases that contribute to the total global warming? 

  • CFC 14%, CH4 20%

  • CO2 40% CFCs 30%

  • N2O 6%, CO2 86%

  • CH4 20% N2O 18%


A.

CFC 14%, CH4 20%

The gases, which are transparent to solar radiation but retain and partially reflect back long wave heat radiations are called greenhouse gases. Recently, the concentration of green -house effect that is resulting in increases the mean global temperature. It is called global warming. The various greenhouse gases are CO2 (warming effect 60%) CH4 (20%)<CFC (14%) and nitrous oxide - N2O (6%)

The gases, which are transparent to solar radiation but retain and partially reflect back long wave heat radiations are called greenhouse gases. Recently, the concentration of green -house effect that is resulting in increases the mean global temperature. It is called global warming. The various greenhouse gases are CO2 (warming effect 60%) CH4 (20%)<CFC (14%) and nitrous oxide - N2O (6%)


Which of the following pollutants is not produced by exhaust of motor vehicles ?
  • CO
  • Hydrocarbon
  • Fly-ash
  • NO

C.

Fly-ash

Ozone depletion will cause :
  • Forest fire
  • Pneumonia
  • Increased incidence of skin cancer
  • None of these

C.

Increased incidence of skin cancer

The meaning of BOD is :
  • Bacterial oxygen demand
  • Biological optimum density
  • Biochemical oxygen demand
  • Bioorganisation decay

C.

Biochemical oxygen demand

In the scrubber in the electrostatic precipitator the gases are passed through :
  • filter
  • lime
  • spray of water
  • both 2 and 3

D.

both 2 and 3

What is the term for the inflammation of cornea due to high absorption of UV-B radiation :
  • myopia
  • snow blindness
  • biomagnification
  • None of the above

B.

snow blindness