How to build a solar still
  • 1. What is the primary purpose of a solar still?
A) To generate electricity
B) To purify water using sunlight
C) To cool water in hot climates
D) To heat water for showers
  • 2. What is the most common material used for the transparent cover of a solar still?
A) Aluminum foil
B) Cardboard
C) Wood
D) Glass or clear plastic sheeting
  • 3. What is the function of the collection trough in a solar still?
A) To heat the contaminated water
B) To provide structural support
C) To block sunlight
D) To collect the condensed water
  • 4. What color is most effective for the basin of a solar still to absorb heat?
A) Silver
B) White
C) Black
D) Clear
  • 5. What type of energy powers a solar still?
A) Electrical energy
B) Mechanical energy
C) Solar energy
D) Chemical energy
  • 6. What process causes the water to condense inside the solar still?
A) Filtration
B) Reverse osmosis
C) Evaporation and condensation
D) Chemical reaction
  • 7. What type of water should be used in a solar still?
A) Deionized water
B) Clean drinking water
C) Contaminated or brackish water
D) Distilled water
  • 8. Why is a tight seal important for a solar still?
A) To allow for ventilation
B) To attract more sunlight
C) To prevent water vapor from escaping
D) To reduce condensation
  • 9. What is the ideal angle for the transparent cover of a solar still in relation to the sun?
A) Any angle is sufficient
B) Perpendicular to the sun's rays
C) Parallel to the ground
D) At a 45-degree angle
  • 10. What safety precaution should be taken when using glass for a solar still?
A) Use a magnifying glass to focus sunlight
B) No precautions are necessary
C) Handle with care to avoid breakage
D) Wear sunscreen
  • 11. What increases the efficiency of a solar still?
A) Using cold water
B) A smaller surface area for evaporation
C) Using reflective materials inside the still
D) A larger surface area for evaporation
  • 12. Which material is suitable for the basin of a solar still?
A) Dark-colored plastic or metal
B) Mirrored surface
C) Clear glass
D) White cloth
  • 13. What is a common environmental benefit of using a solar still?
A) Reduced reliance on fossil fuels for water purification
B) Increased carbon emissions
C) Depletion of water resources
D) Land degradation
  • 14. What is the approximate yield of a simple solar still per day?
A) 1-3 liters per square meter
B) Less than 0.1 liter per square meter
C) 50-100 liters per square meter
D) 10-20 liters per square meter
  • 15. Why is it important to clean the inside of the transparent cover regularly?
A) To collect more water
B) To maintain transparency and sunlight penetration
C) To increase humidity inside the still
D) To prevent algae growth
  • 16. In what type of climate are solar stills most effective?
A) Cold and cloudy climates
B) Polar climates
C) Sunny and warm climates
D) Humid and rainy climates
  • 17. What type of impurities does a solar still effectively remove?
A) Viruses
B) Radioactive isotopes
C) Dissolved gases
D) Salts, bacteria, and heavy metals
  • 18. What is the function of the angle of the transparent cover?
A) Reflects sunlight away from the still.
B) Provides structural support to the still.
C) Traps heat inside the still.
D) Facilitates the flow of condensed water to the collection trough.
  • 19. Which of the following is NOT a key component of a basic solar still?
A) A transparent cover
B) A basin
C) A water pump
D) A collection trough
  • 20. What is the primary reason for using a dark-colored basin?
A) To prevent algae growth
B) To absorb more solar radiation and heat up the water faster
C) To reflect sunlight and keep the water cool
D) To make the still more aesthetically pleasing
  • 21. How does a solar still separate water from contaminants?
A) By chemically treating the water
B) By boiling the water and collecting the steam
C) By filtering the water through a membrane
D) By evaporating the water and leaving the contaminants behind
  • 22. What maintenance is required for a solar still?
A) Annual lubrication of moving parts
B) Daily draining and refilling of the basin
C) Regular cleaning and occasional replacement of the transparent cover
D) No maintenance is required
  • 23. Why is ventilation usually avoided in a simple solar still design?
A) To allow for temperature regulation
B) To prevent the buildup of pressure
C) To prevent water vapor from escaping and reduce condensation efficiency
D) Ventilation is always necessary for optimal performance.
  • 24. What is the relationship between the size of a solar still and its output?
A) Size has no impact on output
B) Smaller solar stills are always more efficient
C) Larger stills are less efficient due to heat loss
D) Larger solar stills generally produce more purified water
  • 25. How does ambient temperature affect the performance of a solar still?
A) Lower ambient temperatures are always preferable
B) Higher ambient temperatures generally increase the rate of evaporation
C) Higher temperatures always damage the components.
D) Ambient temperature has no effect on performance
  • 26. What is a potential drawback of using a solar still?
A) Relatively low output compared to other water purification methods
B) Risk of explosion
C) High operating costs
D) Complex construction requirements
  • 27. What factor dictates how much dirty water can be put inside the solar still to work effectively?
A) The sun's strength
B) The water level shouldn't be too high, as this can reduce the surface area available for evaporation.
C) The size of the water container
D) The air temperature
  • 28. Why should water collected from a solar still be stored properly?
A) To prevent recontamination
B) To improve its taste
C) To reduce its temperature
D) To increase its purity further
  • 29. What is the most important factor when choosing a location for a solar still?
A) A level surface
B) Proximity to a water source
C) Access to direct sunlight
D) Protection from wind
  • 30. What is a benefit of using plastic sheeting rather than glass for the transparent cover?
A) Plastic sheeting is always cheaper than glass.
B) Plastic sheeting is more transparent than glass.
C) Plastic sheeting is a better insulator than glass.
D) Plastic sheeting is generally more durable and less prone to breakage.
Created with That Quiz — the site for test creation and grading in math and other subjects.