Science Grade 6 Energy Transfer Through the Water Cycle 3.1 Lesson 3 скачать в хорошем качестве

Science Grade 6 Energy Transfer Through the Water Cycle 3.1 Lesson 3

Activity6 Energy Transfer and the Water Cycle Put v or x 1.All living organisms need water to survive 2.Solar energy and gravity are factors affect the movement of water in the water cycle 3.Melting and freezing are two processes occur when water particles lose thermal energy Importance of water Humans, animals and plants need fresh water to survive. The water we need to live on Earth can be found in rivers, some lakes, . etc Most of plants depend on rain that falls from the clouds in the sky to grow The water cycle in nature The water cycle provides water for all living organisms and regulates weather on our planet Nature recycles water, where the water cycle includes the continuous movement of water from their different resources to the atmosphere, then this water finally drops back to Earth in the form of rain, sleet, snow or hail You have known from the previous activities the processes and steps that form and affect the water cycle which are evaporation, condensation, precipitation, runoff and collection The total amount of water on Earth does not change even if water changes from one state to another Because it can be replaced (recycled) through the water cycle 1Evaporation The heated liquid water over oceans, lakes and rivers evaporates and changes into water vapor 2Condensation The water vapor rises up to the atmosphere, then it cools and condenses into water droplets in the form of clouds Precipitation The water falls to Earth in the form of rain, sleet, snow or hail (snow pellets) Runoff The water flows along Earth's surface into the river and then into the ocean or sea Collection Water collects in streams, rivers, lakes or oceans, then it evaporates and the water cycle starts again You have learned from the previous studies that there are different ways of heat transfer Convection is one way by which heat can transfer Convection: It is the process in which heat transfers in liquids and gases, where hot molecules (less density) rise upward, while colder molecules (more density) fall down The heat of the Sun transfers from space to Earth's atmosphere by radiation This heat can transfer through Earth's atmosphere also by convection in the form of convection currents The unequal heating of land and oceans causes difference in temperatures and densities in water of oceans and atmosphere Convection in liquids and gases When a liquid or gas is heated, it expands and becomes less dense, and lighter, so it rises upward While the cold liquid or gas is more dense, so it moves downward and replaces the warm liquid or gas The warm liquid or gas that moves upward and the cold liquid or gas that moves downward form a cycle of convection currents The force of gravity helps in the rising and falling of different densities of liquids and gases which leads to the rotation of convection currents causing the formation of wind and ocean currents Convection currents in Earth's atmosphere help in determining the regional climate The relationship between convection and condensation Convection causes the rising of temperature of air that contains water vapor Condensation happens when this rising air loses its heat and the cold water vapor changes into water droplets and finally this leads to formation of clouds 5Put (v) or (x) 1The warm air moves downward, while the cold air moves upward. 2 Precipitation is the process in which water falls on Earth in the form of rain, snow or sleet 3Evaporation is the process in which matter changes from gas state to liquid state Condensation and freezing are two processes occur when water particles lose thermal energy Evaporation, melting and transpiration are processes occur when water particles gain thermal energy Gravity is a force affects the movement of water in the water cycle Getting closer to the equator or moving away from it affects the weather, The weather of the areas near the equator is hot and humid The weather of the areas as we move away to north and south of the equator depends on the temperature and precipitation at these areas, The weather could be warm and humid Or, the weather could be freezing cold Some areas on Earth have very little rains and this causes the formation of large areas of deserts Now, let's study how the inclination of sun rays affects the weather. In figure1,when the sun rays fall perpendicular on Earth's surface in the area near the equator, the sun rays are concentrated on a small area giving high effect of heat, so the weather is hot In figure2,when the sun rays fall semi-inclined (semi-slanted) on Earth's surface in the area at the north and south of the equator, the sun rays are distributed on a large area giving low effect of heat, so the weather is warm In figure3, when the sun rays fall very Incline inclined (very slanted) on Earth's surface in the area far away from the equator, the sun rays are distributed on a very large area giving the lowest effect of heat, so the weather is very cold #science #grade6 #egypt #المعاصر #شرح_المعاصر