1. Tardigrade
  2. Question
  3. Biology
  4. How many of the following statements are correct? 1. Good ozone is found in the stratosphere. 2. UV radiation having a lower wavelength than UV–B is almost completely absorbed by the Earth’s atmosphere. 3. UV–B causes snow blindness and cataract. 4. dB is a unit to measure the thickness of ozone.

Q. How many of the following statements are correct?
Good ozone is found in the stratosphere.
UV radiation having a lower wavelength than UV–B is almost completely absorbed by the Earth’s atmosphere.
UV–B causes snow blindness and cataract.
dB is a unit to measure the thickness of ozone.

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Solution:

Good ozone is formed in the stratosphere and it acts as a shield absorbing UV rays coming from the sun. UV radiation having a lower wavelength than UV - B are almost completely absorbed by the Earth’s atmosphere, given that the ozone layer is intact. UV B causes inflammation of the cornea, called snow- blindness, cataract, etc. The thickness of the ozone in a column of air from the ground to the top of the atmosphere is measured in terms of Dobson units (DU) and dB is known as decibels is used to measure the amounts of acoustics.