Chapter-14 water exampler

Explanation:

The correct option is (a) Drying wet clothes

Drying wet clothes simply involves removing moisture from the clothes by exposing them to air or heat, and does not require the addition of water.

Cleaning utensils, bathing, and washing clothes, on the other hand, all involve the use of water. Cleaning utensils and washing clothes require the addition of water to remove dirt and stains, while bathing involves using water to cleanse the body.

Explanation:

The correct option is (c) Brushing teeth 

Mopping a room typically requires a significant amount of water to wet the mop and clean the floor, while washing clothes and bathing require even larger quantities of water.

Brushing teeth, on the other hand, typically only requires a small amount of water to wet the toothbrush and rinse the mouth. To conserve even more water while brushing teeth, one can turn off the tap while brushing and only turn it on when rinsing.

Explanation:

The correct option is (b) Two glasses

Two glasses of water is required to make one page of paper but it can vary depending on the quality and thickness of the paper.

Explanation:

The correct option is (a) River, lakes or well

Water from rivers and lakes is often treated and purified at a water treatment plant before it is distributed to households through a network of pipes. The water is typically drawn from the source, treated to remove impurities, and then pumped to storage tanks and reservoirs before being distributed to households.

Water from wells, on the other hand, is typically pumped from an underground aquifer or well, which is a natural underground source of water. Depending on the location, the well may be dug by hand or drilled using heavy equipment. The water is then pumped to the surface and treated to remove any impurities before being distributed to households.

Explanation:

The correct option is (d) A glass of water kept in a room.

Out of the given options, the slowest rate of evaporation of water will be in the case of a glass of water kept in a room because there is a lower temperature and lower air flow in a room than the other options.

In option (a), the bucket of water kept on the rooftop is exposed to sunlight and wind, which increases the rate of evaporation.

In option (b), the tray of water kept in sunlight has a large surface area exposed to the sun's heat and air, which increases the rate of evaporation.

In option (c), the kettle of water kept on a burner has a high temperature and is exposed to heat, which increases the rate of evaporation.

Explanation:

The correct option is (b) release water vapor

Transpiration is a process in which plants release water vapor into the atmosphere through tiny pores on their leaves called stomata.

This process is essential for the survival of the plant as it helps to regulate the plant's temperature, transport nutrients, and maintain its structure.

Transpiration also plays an important role in the water cycle, as the water released by plants contributes to the moisture in the atmosphere, which can later fall as precipitation and replenish the water in the soil.

Explanation:

The correct option is (c) tiny drops of water floating in air.

Clouds are formed when warm, moist air rises and cools, causing the water vapor in the air to condense into tiny water droplets or ice crystals. These droplets or crystals then come together to form clouds.

Clouds can take on many different shapes and sizes, depending on the weather conditions and the altitude at which they form. They can range from wispy, high-altitude cirrus clouds to low-lying stratus clouds, which can sometimes bring rain or snow.

Explanation:

The correct option is (c) Groundwater

Wells are supported by groundwater.

Groundwater is water that is stored in porous rock formations or soil, typically beneath the Earth's surface. Wells are typically drilled or dug into the ground to reach this water, which can then be pumped to the surface for use.

Groundwater can come from a variety of sources, including rain and snowmelt that seeps into the ground and is stored in underground aquifers. The water in these aquifers can be replenished over time as more precipitation falls and percolates into the ground.

Wells can provide a reliable source of water for households, farms, and communities in areas where surface water sources like lakes and ponds may be scarce or unreliable.

Explanation:

The correct option is (d) all of the above

Floods can be caused by heavy rainfall, snowmelt, storm surges, or dam failures, and can lead to extensive damage and destruction. When floodwaters rise rapidly, they can pose a significant threat to human life, causing drowning and other injuries. Floods can also damage or destroy homes, businesses, and other infrastructure, leading to significant economic losses.

Domestic animals can also be impacted by floods, as they may be stranded or swept away by floodwaters, or may suffer from exposure to cold and wet conditions. Floods can also cause significant damage to crops, destroying fields and making it difficult for farmers to grow or harvest their crops.

Explanation:

The correct option is (b) Rainwater harvesting

Rainwater harvesting is the practice of collecting and storing rainwater for later use. The idea behind rainwater harvesting is to capture water where it falls, typically on rooftops or other impermeable surfaces, and store it in tanks or other storage containers.

Rainwater harvesting can be a sustainable and cost-effective way to supplement traditional water sources, particularly in areas where water is scarce or unreliable. It can also help to reduce the amount of runoff and erosion caused by heavy rainfall, and can contribute to groundwater recharge.

By capturing and storing rainwater, communities and households can become more self-sufficient when it comes to water, reducing their reliance on expensive or unsustainable sources like groundwater pumping or municipal water supplies.

Explanation:

The activities shown in figure are:

1. Water is being used for bathing, water is a crucial element in our daily routine for maintaining personal hygiene and cleanliness. Bathing is one such activity that requires the use of water to wash away dirt, sweat, and other impurities from our skin.

2. Clothes are being washed using water, which is an essential component of the cleaning process, to remove dirt and stains.

Washing clothes is an important household chore that involves the use of water to remove dirt, stains, and other impurities from the fabric. Water plays a crucial role in the cleaning process by dissolving dirt and other particles and rinsing them away from the clothes.

3. Groundwater is being lifted from wells and stored for drinking and other purposes.

Groundwater is a vital resource for drinking and other purposes, such as irrigation and industrial use. Wells are often used to access groundwater, which is lifted to the surface and stored in tanks or other storage containers for later use. This ensures a reliable and sustainable source of water for communities and households that may not have access to other sources of water.

Explanation:

Two activities that require more than a single bucket of water:

1. Watering a garden or lawn: Depending on the size of the garden or lawn, watering it can require a significant amount of water. For example, a small garden may require several buckets of water, while a large lawn may require several hundred gallons of water.

2. Filling a swimming pool: Filling a swimming pool can require a large amount of water, depending on the size of the pool. For example, an average-sized swimming pool can hold anywhere from 10,000 to 30,000 gallons of water, which is much more than what can be filled with just a bucket of water.

Explanation:

Two activities that require less than a single bucket of water:

1. Watering a small plant: Watering a small potted plant typically requires less than a bucket of water, depending on the size of the plant and the pot.

2. Washing hands: Washing hands is an essential activity that requires very little water, usually less than a bucket. It is recommended to use only a small amount of water to wash hands to avoid wastage.

Explanation:

When wet clothes are placed on a clothesline, they get dry after some time due to the process of evaporation. Evaporation is the process in which a liquid, in this case, water, changes into a gas, which is water vapor.

As the wet clothes are exposed to the air, the water molecules on the surface of the clothes absorb heat energy from the surroundings, which causes them to gain enough energy to break the and escape into the air as water vapor. The water molecules continue to evaporate until all the water has been converted to water vapor.

The rate of evaporation depends on various factors such as temperature, humidity, air movement, and surface area. Higher temperatures, lower humidity, and air movement increase the rate of evaporation, which leads to faster drying of clothes. Conversely, cooler temperatures, higher humidity, and stagnant air slow down the rate of evaporation, which leads to slower drying of clothes.

In summary, wet clothes placed on a clothesline get dry after some time due to the process of evaporation, which causes the water on the surface of the clothes to change from a liquid state to a gaseous state and escape into the air.

Explanation:

Even though the water is not directly exposed to sunlight, the air around the water is still warmer than the water itself. This is because the air is warmed by contact with the tree, which absorbs sunlight and converts it to heat. As a result, the air surrounding the water molecules gets heated and the water molecules gain enough energy to break the surface tension of the water and evaporate into the air.

Water kept in the shade of a tree can also undergo evaporation due to the process of diffusion. Diffusion is the movement of molecules from a region of higher concentration to a region of lower concentration. In this case, the water molecules on the surface of the water have a higher concentration than the surrounding air molecules.

Moreover, the shade of a tree reduces the amount of direct sunlight reaching the surface of the water, which reduces the rate of evaporation. However, it also reduces the wind speed, which can create a microclimate that is more humid than the surrounding areas. This can slow down the rate of evaporation even further.

In conclusion, water kept under the shade of a tree can also undergo evaporation due to surrounding heat and wind movements and also by the process of diffusion, as the surrounding air molecules get heated and the water molecules gain enough energy to evaporate into the air.

Explanation:

The presence of concrete cover over areas can significantly affect the accessibility of groundwater in various ways.

Firstly, concrete is impermeable, meaning that water cannot pass through it easily. As a result, rainwater cannot seep into the ground and replenish the groundwater table. This can lead to a reduction in the amount of water available for human consumption and agricultural activities.

Secondly, concrete surfaces often have a higher rate of runoff compared to natural surfaces such as soil or vegetation. This means that when it rains, the water flows over the concrete and into drainage systems, instead of being absorbed by the ground. This can lead to flash floods, erosion, and can also reduce the amount of water that is able to infiltrate the ground and replenish the groundwater table.

Lastly, concrete surfaces also contribute to the urban heat island effect, where cities and urban areas experience higher temperatures than surrounding rural areas. This increase in temperature can lead to increased evaporation rates, reducing the amount of available groundwater even further.

In summary, the presence of concrete cover can impact the accessibility of groundwater by reducing the amount of water that infiltrates into the ground, increasing runoff rates, and contributing to the urban heat island effect.

Explanation:

There are several reasons why conservation of water is very crucial. Here are two main reasons:

1. Limited availability: The earth's surface is mainly covered by water, but only a small percentage of it is freshwater that is available for human consumption. With a growing population and increasing demand for water, the supply of freshwater is becoming limited. Thus, conserving water is necessary to ensure that there is enough water to meet 

the needs of present and future generations.

2. Environmental impact: Water conservation also plays an important role in minimizing the impact of human activities on the environment. For example, using excessive water for irrigation can lead to soil salinization and degradation, affecting crop productivity. Excessive water use can also deplete natural water sources such as rivers and lakes, harming aquatic life and ecosystems. By conserving water, we can reduce the amount of water we take from the environment and minimize our impact on it.

Overall, water conservation is essential to ensure that we have access to enough water for our needs and to reduce our impact on the environment.

Explanation:

Water, as vapor goes into atmosphere by the processes of evaporation and transpiration and 

forms clouds, which on condensation fall in the form of rain and snow.

Explanation:

The majority of the water that falls on land as rain and snow eventually returns to the sea or ocean through the process of the water cycle. After precipitation occurs, the water can either seep into the ground to replenish underground water sources or flow over the surface of the land as runoff. This runoff can collect in rivers, lakes, and other bodies of water, eventually making its way to the ocean.

In addition, a significant amount of water is returned to the atmosphere through the process of evapotranspiration, where water from the soil and plants is evaporated and transpired back into the air.

Once the water reaches the ocean, it can be transported by ocean currents and used for various processes such as cooling the Earth's surface, driving weather patterns, and providing habitat for marine life. The water cycle is a continuous process that ensures the constant circulation and availability of water on Earth.

Explanation:

Diagram showing the water cycle:

Explanation:

You can retrieve salt from the solution by the process of evaporation.

Here are the steps to follow:

1. Heat the solution in a pan until the water starts to boil.

2. Reduce the heat and let the solution simmer until all the water has evaporated, leaving behind salt crystals.

3. You can use a strainer to filter the salt crystals from any remaining water.

4. Spread out the salt crystals on a clean surface and let them dry completely.

5. Once dry, you can collect the salt and store it in an airtight container.

Explanation:

Rooftop rainwater harvesting is a simple process that involves the collection and storage of rainwater that falls on rooftops. The collected rainwater can be used for various purposes like watering plants, washing clothes, and even for drinking after proper treatment.

The process involves the following steps:

1. Collection: The first step is to collect rainwater from the rooftop. The roof is designed to channel rainwater into gutters that lead to downspouts. The downspouts carry the rainwater to a storage tank or reservoir.

2. Filtration: Once the rainwater is collected, it needs to be filtered to remove any debris or contaminants. This is typically done through a filter system, which can range from simple mesh screens to more complex filtration systems.

3. Storage: The filtered rainwater is then stored in a tank or reservoir for later use. The storage tank can be placed above or below ground, depending on the available space and the needs of the household or building.

4. Distribution: The stored rainwater can be distributed through a gravity-fed system or a pump system. Gravity-fed systems use the force of gravity to move the water to the desired location, while pump systems use a pump to distribute the water.

By harvesting rainwater from rooftops, the process can help to reduce the demand on traditional water sources such as groundwater and surface water. Additionally, it can help to mitigate the effects of urbanization and climate change by reducing the amount of stormwater runoff that enters local waterways.