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jiD.Answer the following questions in brief., 1. Name the hottest planet in our solar system. Is it closest to the sun?, Ans. Venus is the hottest planet in our solar . It is second closest planet., 2. How much time does the Earth take --i. Revolve once around the sun., ii. To complete one rotation about its own axis., Ans.i.365 days and 6 hours, ii.24 hours, 3. State the nature of the shape of orbit of planets., Ans. The path is nearly circular in shape., 4. Write the meaning of the term “artificial satellite”., Ans. Artificial satellite are man made object which can be made to revolve around the earth., E. Answer the following questions., 1. How is the sun useful to us?, Ans. Sun is useful to us in many ways, i., ii., iii., iv., v., , It gives out energy in the form of heat and light., The sun is essential for growth and maintenance of all forms of life on the earth., All living beings whether plants or animals depend on the sun for their food., Plants make their food in the presence of Sunlight., We use solar energy in many ways like solar cookers solar geyser and solar cells ., , 2. Name the Terrestrial planets why are they so ?, Ans. Mercury, Venus Earth, Mars are Terrestrial planets . These planets are mostly made up of Rocks, and metal. Hence these planets are also called Terrestrial planets., 3. State the conditions necessary for existence of life on a plaanet., Ans. These conditions are, i., ii., iii., , Presence of atmosphere., Presence of water on the surface, Right size and right distance from the sun that enables it to receive just the correct amount, of solar ., 4.Why do we observe phases of moon?, Ans. We observe phases of moon because of the changes in the relative position of the, Earth and the Moon with respect to sun.

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5. State two uses of to which artificial satellite being put., Ans. To uses are—, i., They are used in communication for transmitting radio telephone and television ., ii., They are also used for weather forecasting and Remote sensing.