1. How much of the Earth is covered with water?
๐ About 71%
2. What is the main source of water on Earth?
๐ Oceans
3. What percentage of water is saline?
๐ About 97%
4. What percentage of water is freshwater?
๐ About 3%
5. Where is most freshwater found?
๐ Glaciers and ice caps
6. Name two sources of freshwater.
๐ Rivers, lakes
7. What is the water cycle?
๐ Continuous water movement
8. Name the first stage of water cycle.
๐ Evaporation
9. What is evaporation?
๐ Water changing to vapour
10. What is condensation?
๐ Vapour to water
11. What is precipitation?
๐ Falling of water
12. Name one form of precipitation.
๐ Rain
13. What is transpiration?
๐ Water loss from plants
14. What are ocean waters called?
๐ Saline water
15. Why is ocean water salty?
๐ Dissolved salts
16. Name the three major oceans.
๐ Pacific, Atlantic, Indian
17. What are waves?
๐ Rising and falling water
18. What causes waves?
๐ Wind
19. What are tides?
๐ Rise and fall of sea
20. What causes tides?
๐ Gravitational pull
21. Which heavenly bodies cause tides?
๐ Moon and Sun
22. What are ocean currents?
๐ Flowing ocean water
23. Name one warm ocean current.
๐ Gulf Stream
24. Name one cold ocean current.
๐ Labrador Current
25. What is groundwater?
๐ Water below surface
26. How is groundwater recharged?
๐ Rainwater seepage
27. What is water scarcity?
๐ Shortage of water
28. Name one cause of water scarcity.
๐ Overuse
29. How can we conserve water?
๐ Save and reuse
30. Why is water important?
๐ Supports life
๐ Quick Revision Tricks
๐ Water Cycle:
E-C-P โ Evaporation โ Condensation โ Precipitation
๐ Ocean Movements:
W-T-C โ Waves โ Tides โ Currents