Free Environment and Atmosphere MCQs with Answers

1. The ozone layer is found in which layer of the atmosphere?

• A. Troposphere
• B. Stratosphere
• C. Mesosphere
• D. Thermosphere

Explanation: The ozone layer lies in the stratosphere, roughly 15 to 35 kilometres above the earth, where it absorbs most of the sun’s harmful ultraviolet radiation. The troposphere below it is where weather occurs.

2. Pedology is study of ___________?

• A. Birds
• B. Languages
• C. Soils
• D. None of these

Explanation: Pedology is the scientific study of soil, including its formation, composition, classification, and distribution. The related term edaphology focuses more on soil in relation to plant growth.

3. There are many different types of frozen water on Earth. Collectively, they are known as the: ___________?

• A. Hydrosphere
• B. Cryosphere
• C. Frigid Zone
• D. Biosphere

Explanation: The cryosphere includes all frozen water on Earth, including glaciers, ice sheets, sea ice, snow and permafrost. The hydrosphere covers Earth’s water in all states, not only frozen water.

4. The sky appears blue because the earth's atmosphere __________?

• A. Scatters blue light
• B. Reflects blue light
• C. Transmits blue light
• D. Has actual blue cover

Explanation: Air molecules scatter the shorter blue wavelengths more strongly than the longer red wavelengths, so blue light reaches the observer from many directions. The atmosphere does not have a blue covering and the effect is not ordinary reflection.

5. Which one of the following is the main culprit in the thinning of Ozone layer in the earth's stratosphere?

• A. Carbon dioxide
• B. Chlorofluorocarbons
• C. Nitrogen oxides
• D. Methane

Explanation: Chlorofluorocarbons reach the stratosphere, where ultraviolet radiation releases chlorine atoms that catalytically destroy ozone. Carbon dioxide and methane mainly contribute to warming rather than being the principal cause of ozone thinning.

6. The severity of 2005 earthquake in Pakistan on Richter scale was ?

• A. 6.9
• B. 7.6
• C. 7.1
• D. none

Explanation: The 8 October 2005 Kashmir earthquake in Pakistan had a commonly reported magnitude of 7.6 on the Richter scale. The nearby values 6.9 and 7.1 do not match the standard reported magnitude.

7. The unit to measure the quantity of Ozone in atmosphere is?

• A. Dobson
• B. Dalton
• C. Cuolomb
• D. none

Explanation: The Dobson unit measures the total amount of ozone in an atmospheric column. Dalton is a unit of atomic mass, while coulomb measures electric charge.

8. The earth's ___________ is divided into 15 major plates of various sizes

• A. Mesosphere
• B. Stratosphere
• C. Lithosphere
• D. None

Explanation: The lithosphere is the rigid outer layer of Earth and is broken into major and minor tectonic plates. The mesosphere and stratosphere are atmospheric layers, not the plates themselves.

9. UV light falls in the category of___________?

• A. Ionizing Radiations
• B. Non Ionizing Radiation
• C. Visible light
• D. None

Explanation: Ultraviolet radiation is conventionally grouped as non-ionizing radiation in basic science because most UV lacks enough energy to remove electrons from atoms. Very high-energy extreme UV can approach or produce ionization, but that exception is not intended here.

10. Equator passes through one of these countries___________?

• A. Saudi Arabia
• B. Italy
• C. Japan
• D. None

Explanation: The Equator crosses countries such as Ecuador, Kenya, Indonesia and Brazil, but it crosses none of the three countries listed. Hence, 'None' is correct.