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SAI INTERNATIONAL SCHOOL
                                                        Class-6

                                                   Lesson Notes
                                                  Subject-Physics
                                      Ch.- Water: The Life-giving Liquid
                             Subtopic- Droughts, Floods and Water Pollution

               Droughts:
                      During summer, sometimes rain doesn't happen for a long period of time. This
                       leads to scarcity of water. With times, the rivers and lake start to dry up. The
                       soil also becomes dry due to transpiration through plants and there is no
                       addition of water. This condition is called drought.
                      As a result of droughts, plants and animals die due to lack of food and
                       starvation. This period of time is called famine.






















               Floods:
                      Sometimes, heavy rainfall over a period of days causes rivers to flow beyond
                       their banks and water spills onto the land. This condition is called flood.
                      The affected areas are often covered and contaminated with hazardous
                       materials, such as sharp debris, pesticides, fuel and untreated sewage.
                      It leads to outbreaks of deadly waterborne diseases such as typhoid,
                       hepatitis-A and cholera, leading to epidemics.
                      An epidemic is an infectious disease that affects thousands of people at the
                       same time in a particular region.
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