D] The Lunar eclipse; The shadow cast by the Earth on the moon during Lunar eclipse is always circular proving the Erath is a sphere.

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1 GEOGRAPHY THE SHAPE OF THE EARTH Std What is the shape of the Earth? It is spherical in shape although not a perfect sphere because it is it bulges at the equator and is slightly flattened at the poles. hence its shape is termed as an oblate spheroid. [Geoid] 2. Why does the Earth have the above shape? Because of the centrifugal force caused due to the rotational movement of the Earth. 3. Provide any three evidences to prove the Earth is a Sphere. A] Circum navigation of the Earth: Magellan ship completed round the world voyage where he started from Spain and returned to Spain the same place he started this would not happen if the Earth was flat. B] Circular horizon: While standing at the sea shore and seeing a ship approaching we first see the mast then the deck and then the funnel. If the earth were flat we would see the whole ship. C] Sunrise and sunset; The sun rises and sets at different times in different places. As the Earth rotates from west to East places in east see the sun earlier. If the Earth were flat the whole world would shave sunrise and sunset at the same time. D] The Lunar eclipse; The shadow cast by the Earth on the moon during Lunar eclipse is always circular proving the Erath is a sphere. E] Aerial Photographs;

2 Pictures taken by by Satellites show clearly the curved edge of the earth. This is the most convincing proof. F] The Bedford level experiment The Bedford Level Experiment was a series of observations carried out along a sixmile length of the Old Bedford River The river was a slow-flowing drainage canal running in uninterrupted straight line. The most famous of the observations, involved a set of three poles fixed at equal height above water level along this length. When the poles were viewed from one end of the canal to the other the middle pole looked slightly higher. This could not have happened if the earth were flat G] The Pole Star The pole star is seen at an angle of 90 degrees at the North pole and ist angle decreases towards the equator.at the equartor the angle is 0 degrees.this is only possible if the Earth were an arc otherwise the Pole star would have the same height for all latitudes 4.What makes the Earth a Habitable / livable Planet? In what way is the Atmosphere beneficial to man?[refer to point C] The Earth supports life because of: A] Its optimum distance from the Sun :It is neither too hot nor too cold. If it was too close to the sun all living thing would perish and if it was too far it would freeze. B] Temperatures; The Earth being third planet away from the sun has an average temperature of 17degrees Celsius which is suited for life to exist. Mercury and Venus shave temperatures soaring to 400, Venus has very high temperature because it atmosphere is composed of carbon dioxide. It creates a greenhouse effect. C]Atmosphere: The Atmosphere covers the earth like a protective Blanket. It receives heat from the sun in form of solar radiation and loses some of it not all by earths radiation so it maintains a balance of temperature and helps keep the Earth s surface warm. The atmosphere also supports life because it consists of life supporting gases like Oxygen, Nitrogen and Carbon dioxide. The Ozone in the atmosphere absorbs the ultra violet rays of the sun. D]Water:

3 70% of Earth s surface consists of water which moderates the climate on the Earth. During day water absorbs a lot of heat thus earth remains quite cool. Water bodies like seas and rivers cause precipitation without which life would be impossible. 5.Why is the earth called a watery planet? Because it surfaces consists of 70% of water in form of rivers seas and oceans. 6.Define the Following: Lithosphere; The layer of on the surface of the earth. Biosphere; The parts of the land, sea, and atmosphere in which organisms are able to live. This sphere is at the junction of of Atmosphere, Lithosphere and Hydrosphere Therefore it is the sum of all ecosystems on the Earth

4 7] A] What does the given diagram depict? Carbon cycle B] How does carbon exist in the Atmosphere? In the form of Carbon. C]In the above diagram which living form is taking in the carbon present in the atmosphere The Trees D] How is it replenished into the atmosphere? Through forests. burning of fossil fuels, respiration of animals.

5 Modify environment Source of energy PHOTOSYNTHESIS producers 8] a. What is the relationship between living and nonliving things as seen in the Pyramid above which shows the nutrition cycle? They are all interdependent. b.name the two categories into which the living things are divided? Producers and consumers c.name the process which enables plants to produce food. Photosynthesis d.name the two categories of consumers who live on producers? Herbivores and carnivores. e. Name the living organism who can modify the food chain? Man f. What does the above figure of the pyramid show? The Nutrition cycle. *****************************************************