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Solutions of practice worksheet 2 (class 6) Q 1:- Short answer questions:          (2x7=14 marks) i)   Can you think of creating a shape that would give a circular shadow if held in one way and a rectangular shadow if held in another way? Ans. Yes, Cylindrical object kept vertically will give rectangular shadow while Cylindrical object kept horizontally will give circular shadow . ii) Discuss in brief two ways of water harvesting. Ans. Increasing the availability of water is to collect rainwater and store it for later use. Collecting rainwater in this way is called rainwater harvesting.     The two techniques of rainwater harvesting are: 1.      Rooftop rainwater harvesting: In this system the rainwater is collected from the rooftop to a storage tank, through pipes. This water may contain soil from the roof and need filtering before it is used. Instead of collecting rainwater in the tank, the pipes can go directly into a pit in the ground. This then seeps into the soil

  Solutions of practice worksheet 2 (class 7) 1.   Name the acid/base/salt present in the following: a.        Each cell of our body Ans.  Deoxyribonucleic Acid  (DNA) b.       Window cleaner Ans.   Ammonium hydroxide (Base) c.        Chalk powder Ans. C alcium carbonate (Salt) d.       Spinach Ans. Oxalic acid 2.     What are the factors on which the amount of heat produced in a circuit depends? Ans. The amount of heat produced in a circuit depends on its ·          nature of materials used in circuit ·          length of a wire ·          thickness of wire of a wire ·          current passing through circuit 3.     Define : a.        Spectrum Ans.  Band of colous formed after dispersion of light. b.       Refraction Ans. Bending of light when it enters from one medium to another. 4.     Give reasons: a.        Factory waste is neutralized before disposing it into the water bodies. Ans. The wastes of many factories contain acids. If they are allowed to flow into the water bodi

  Solutions of  P RACTICE WORKSHEET 1 (Class 7) Acid turns blue litmus Orange Pink Red green Which of the following is a strong acid? Citric acid Acetic acid Malic acid Sulphuric acid Which one is an organic acid? Hydrochloric acid Lactic acid Sulphuric acid Nitric acid Which one of the following is a natural indicator Oxalic acid. Phenolphthalein Turmeric Methyl orange Product of a neutralisation reaction are always an acid and a salt a salt and a base an acid and a base a salt and water In case of indigestion, we use Antibiotic Antacids Antipyretic Alcohols Sodium hydroxide is found in Petrol Lemon table salt Soap Common salt Turmeric is a natural indicator. On adding its paste to acid and base separately, which colour would be observed Yellow in acid and red in base. Red in acid and blue is base. Yellow in both acid and base. Pink in acid and yellow in base. Sour things contain Bases Salts Neutral Acids Sting of an ant contains vinegar common salt formic acid milk of magnesia In ins