Environmental Physics MCQs

1. : Which radiation is mainly responsible for the greenhouse effect?
(A) Ultraviolet radiation
(B) Visible light
(C) Infrared radiation
(D) Gamma radiation

2. : The average solar constant at Earth’s atmosphere is approximately:
(A) 1361 W/m²
(B) 1000 W/m²
(C) 500 W/m²
(D) 2000 W/m²

3. : The albedo of Earth represents:
(A) Earth’s heat capacity
(B) Fraction of solar energy reflected back to space
(C) Earth’s greenhouse gas absorption
(D) Earth’s rotation speed

4. : Which layer of the atmosphere absorbs most of the UV radiation?
(A) Troposphere
(B) Stratosphere
(C) Mesosphere
(D) Thermosphere

5. : Wien’s displacement law relates:
(A) Pressure and temperature
(B) Wavelength and temperature
(C) Energy and frequency
(D) Mass and energy

6. : Which gas is the most effective absorber of longwave radiation?
(A) Oxygen
(B) Nitrogen
(C) Carbon dioxide
(D) Argon

7. : The greenhouse effect is an example of:
(A) Reflection of solar radiation
(B) Trapping of infrared radiation
(C) Scattering of visible light
(D) Absorption of ultraviolet radiation

8. : The unit of radiant flux density is:
(A) Watt
(B) Joule
(C) Watt per square meter (W/m²)
(D) Joule per second

9. : The main cause of seasons on Earth is:
(A) Distance from the Sun
(B) Tilt of Earth’s axis
(C) Rotation of Earth
(D) Shape of Earth

10. : Which process is responsible for the blue color of the sky?
(A) Reflection
(B) Diffraction
(C) Rayleigh scattering
(D) Absorption

11. : Which type of radiation has the shortest wavelength?
(A) Ultraviolet
(B) Infrared
(C) Gamma rays
(D) Microwave

12. : The Stefan–Boltzmann law is expressed as:
(A) E = σT⁴
(B) E = mc²
(C) E = hf
(D) PV = nRT

13. : What percentage of incoming solar energy is absorbed by Earth’s surface?
(A) ~10%
(B) ~25%
(C) ~50%
(D) ~75%

14. : The greenhouse gases trap heat mainly in which part of the spectrum?
(A) Ultraviolet
(B) Visible light
(C) Infrared
(D) Microwave

15. : Which gas is not a greenhouse gas?
(A) Carbon dioxide
(B) Methane
(C) Nitrogen
(D) Water vapor

16. : The “ozone hole” problem is maximum over which region?
(A) Arctic
(B) Antarctica
(C) Tropics
(D) Europe

17. : Which phenomenon explains why the Sun looks red during sunset?
(A) Diffraction
(B) Refraction
(C) Rayleigh scattering
(D) Polarization

18. : The heat transfer from Sun to Earth takes place by:
(A) Conduction
(B) Convection
(C) Radiation
(D) Evaporation

19. : The main contributor of anthropogenic greenhouse effect is:
(A) Nitrous oxide from fertilizers
(B) Methane from livestock
(C) Carbon dioxide from fossil fuels
(D) CFCs from refrigerators

20. : Which parameter measures the ability of a surface to emit radiation?
(A) Albedo
(B) Emissivity
(C) Absorptivity
(D) Reflectivity

21. : Which gas absorbs both UV and IR radiation?
(A) Ozone
(B) Oxygen
(C) Nitrogen
(D) Argon

22. : What is the average temperature of Earth’s surface (approx.)?
(A) –18 °C
(B) 0 °C
(C) 15 °C
(D) 50 °C

23. : In the absence of greenhouse effect, Earth’s average surface temperature would be:
(A) 15 °C
(B) –18 °C
(C) 0 °C
(D) 30 °C

24. : The fraction of sunlight reflected by Earth’s surface is called:
(A) Emissivity
(B) Albedo
(C) Conductivity
(D) Absorptivity

25. : Which law is used to calculate the wavelength of maximum emission of a black body?
(A) Stefan–Boltzmann law
(B) Wien’s displacement law
(C) Planck’s law
(D) Newton’s law of cooling