V State whether the following statements are True or False
- Water boils at 212oF temperature but, it begins to evaporate at 32oF.[True]
- Mist is not the tiny droplets of water hanging in the air.[False]
- The sub-surface runoff is usually referred as interflow.[True]
TN Board Class 8 Geography Unit 3 Hydrological Cycle QA
VI Answer briefly
Q- Write a short note on aquifer.
A- An aquifer is an underground layer of water-bearing rock that can hold and transmit water. It plays a crucial role in the hydrological cycle by storing groundwater. Aquifers are replenished through infiltration and percolation of surface water, and they can serve as important sources of freshwater for human use and natural ecosystems. The chapter mentions aquifers in the context of runoff, stating that runoff can replenish groundwater as it percolates into an aquifer.
Q- Define “ hydrological cycle”.
A- The hydrological cycle, also known as the water cycle, is defined in the chapter as a global sun-driven process where water is transported from oceans to atmosphere, from atmosphere to land, and from land back to oceans. It’s a continuous process that involves various components such as evapotranspiration, condensation, precipitation, infiltration, percolation, and runoff. This cycle is crucial for the distribution of water on Earth and affects climate, ecosystems, and water availability.
Q- How is the dew formation takes place?
A- Dew formation occurs when water vapor condenses on a relatively cold surface of an object. According to the chapter, dew forms when the temperature of an object drops below the dew point temperature. The dew point is the temperature at which air becomes saturated with water vapor, causing condensation to occur. This process typically happens at night or in the early morning when surfaces cool down.
Q- Write a short note on surface run-off.
A- Surface runoff is one of the three types of runoff mentioned in the chapter. It is defined as the portion of rainfall that enters streams immediately after the rainfall. Surface runoff occurs when rainfall is longer, heavier, and exceeds the rate of infiltration. In this condition, excess water accumulates on the ground surface and moves from one place to another following the land gradient. This overland flow, when it joins streams, channels, or oceans, is termed surface runoff or surface flow. Surface runoff is an important component of the water cycle, contributing to the replenishment of surface water bodies and potentially causing erosion.
