Test: The Water Cycle - Primary 4 MCQ

When clouds become heavy with water droplets, they can no longer hold the moisture, leading to rainfall. This process is a significant part of the water cycle, as it replenishes rivers, lakes, and groundwater, providing essential water resources for all living organisms.

As water vapor rises into the atmosphere, it cools and condenses back into liquid water, forming clouds. This process is crucial for the water cycle, as it leads to precipitation, which is essential for replenishing freshwater resources on Earth.

Freezing is the process where water cools down and transforms into ice. This occurs at 0 degrees Celsius (32 degrees Fahrenheit) under normal atmospheric conditions. Ice is less dense than liquid water, which is why it floats, and it plays a critical role in ecosystems, particularly in polar regions.

The phenomenon where water droplets in clouds unite to form larger drops is known as coalescence. Once these droplets become heavy enough, they fall to the ground as precipitation, such as rain or snow, depending on atmospheric conditions.

The primary energy source that drives the water cycle is the sun. Solar energy heats the water in oceans, rivers, and lakes, causing evaporation. This energy is essential for maintaining the cycle, as it influences temperature and climate patterns worldwide.

The process where water is heated and changes into vapor is called evaporation. This occurs when water molecules gain enough energy from heat to break free from their liquid state and enter the air as water vapor. Interestingly, evaporation is a crucial part of the water cycle, allowing water to move from bodies of water to the atmosphere.

The water cycle significantly influences weather patterns by affecting precipitation and temperature. The movement of water in various states (liquid, vapor, solid) impacts humidity levels, cloud formation, and ultimately the type and amount of precipitation that occurs in different regions.

The sun contributes to the formation of clouds by causing evaporation. When the sun heats bodies of water, it transforms liquid water into vapor, which rises into the atmosphere. As this vapor cools, it condenses into tiny droplets, forming clouds.

The conversion of liquid water to vapor is described by the process of evaporation. This occurs when water is heated, allowing its molecules to gain enough energy to escape into the atmosphere as vapor, playing a key role in the water cycle.

When snow melts, it transforms into liquid water. This process typically occurs when temperatures rise above freezing, allowing the solid snow to change state. The melted snow contributes to rivers and streams, supporting aquatic life and replenishing water supplies.

Condensation primarily occurs when water vapor cools in the atmosphere, allowing it to transition back into liquid water. This process results in the formation of clouds and is crucial for precipitation, which replenishes water sources on Earth.

In colder climates, precipitation often falls as snow. Snowflakes form when water vapor in the atmosphere freezes into ice crystals. This form of precipitation covers landscapes and can significantly affect local ecosystems and water resources when it melts.

Filtration is not a process that is part of the water cycle. The water cycle includes evaporation, condensation, and precipitation, which work together to move water through different states and locations in the environment.

The journey of water from the earth to the sky and back is called the water cycle. This cycle involves various processes, including evaporation, condensation, precipitation, and runoff. Understanding the water cycle is essential for grasping how water is distributed on Earth and how it supports life.

When water vapor cools, it undergoes a process known as condensation, where it turns back into liquid water. This is a key step in forming clouds, as tiny droplets of water coalesce and eventually can lead to precipitation. This process highlights the dynamic nature of water in the water cycle.

Evaporation is defined as the process where liquid water turns into vapor when it is heated. This transformation is a critical component of the water cycle and allows moisture to rise into the atmosphere, where it can later condense and form clouds.

The direct result of condensation in the water cycle is the creation of clouds. When water vapor cools and condenses, it forms tiny droplets that cluster together, resulting in cloud formation. This process is essential for the continuation of the water cycle and for precipitation to occur.

Melting snow plays a critical role in the water cycle by contributing to groundwater supplies and flowing into rivers and streams. This runoff is vital for maintaining water levels in aquatic ecosystems and supporting various forms of life.

The process where rainwater flows into rivers, lakes, and other bodies of water is called runoff. This is an important part of the water cycle, as it helps distribute water across the landscape and can lead to the replenishment of groundwater supplies.

The process of water turning from a solid (ice) back into a liquid is called melting. This typically occurs when temperatures rise above 0 degrees Celsius (32 degrees Fahrenheit). Melting is vital for the water cycle, especially in regions where snow and ice play a significant role in water supply.