Ans=> Geography is the study of the physical features of the earth and its atmosphere, and of human activity as it affects and is affected by these, including the distribution of populations and resources and political and economic activities.
Geography is a study of the Earth and its features. The word Geography is made of two Greek words Geo- which means Earth and Graphy which means- description. So Geography in general sense is the Science that describes the Earth’s surface.
Geography can be further divided into following categories.
• Geo-earth science (topography) –Study of 7 continents present on Earth: Asia, Europe, Africa, North America, South America, Australia & Antarctica.
• Ocean Science- Study of 5 oceans on Earth: North Atlantic Ocean, South Atlantic Ocean, Arctic Ocean, Indian Ocean and Pacific Ocean.
• Climatology- Study of the atmosphere, weather, temperature, heat, heat, decay heat, humidity etc.
Ans=> Global Warming means- Changes in weather & weather patterns on Earth due to the Increase in Temperature of Earth.
This increase in the temperature of the earth (estimated to be 1000F (average) temperature rise over a span of 100 years) results in changes in rain patterns, melting of icebergs and glaciers, rise in sea level, and adverse effects on vegetation and living life.
Causes of Global warming-
Greenhouse gases are the most dominant factor for global warming. These Greenhouse gases absorb heat from other sources such as the Sun causing rise in temperature.
Other major gas which causes global warming is Carbon di-Oxide, which is released along with our out-breathe. It is also produced with the burning of things.
Measures to prevent global warming-
• The emission of CFC gases (used in fridge etc) has to be checked to stop global warming.
• Measures should be taken to prevent pollution due to industrial units.
• To reduce the impact of smoke from vehicles, the environmental standards must be strictly adhered to.
• Renewable energy must be used more extensively.
• There should be a ban on fire in forests.
Ans=> You must have seen the flashing lights in the sky during rainy days. What causes it! Let us see how Lightening works.
There is always some amount of humidity present in the atmosphere. This humidity exists in the clouds as very fine particles of water. There is a kind of friction is always exists between air and water particles. This friction causes the clouds to get charged (of opposite signs).
Some clouds are positive charged and some others are negatively charged. When positive and negative charged clouds come close to each other, then these oppositely charged clouds gets collapsed. Collapsing produces high power. From this, the electricity flows through the air between the two differently charged clouds. This causes lightening.
After the emergence of this glow, we also hear the thunder of clouds as some energy gets converted into sound.
Ans=> Water is available on our planet in three forms solid (ice), liquid (water) and gas (water vapour). But, the amount of water on earth is fixed. There is a cycles in which water passes through all these forms and enables human life to exist. This cycle is called Water Cycle.
In this cycle, water from earth, oceans etc get evaporated (due to sun heat) to form the clouds, water from these clouds comes back to earth as snow or rains. The snow melts & flows into the rivers as water which reaches the oceans again.
Life on earth is possible due to this water cycle.
Ans=> A hydro dam is basically a barrier which stops the flow of water of a river. A huge amount of water gets stored on the upfront of a dam. This stored water is then used for multiple purposes. Electricity productions is one the major use of dams.
Why do we need dams?
Dams are used as storage of water for irrigation, drinking water, electricity generation and rebuilding. Dams also help in flood control.
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