Exercise : Solutions of Questions on Page Number : 252 Q1 : What are the different ways in which water gets contaminated? Answer : Water gets contaminated by the addition of: (i) Agricultural chemicals: Farmers use excessive amounts of pesticides and fertilizers to increase crop production. These chemicals get carried away to the water bodies … Read more
Exercise : Solutions of Questions on Page Number : 234 Q1 : Which of the following is NOT a member of the solar system? (a) An asteroid (b) A satellite (c) A constellation (d) A comet Answer : (c) Constellation A constellation is not a member of the solar system.Constellations are groups of stars that … Read more
Exercise : Solutions of Questions on Page Number : 212 Q1 : Suppose you are in a dark room. Can you see objects in the room? Can you see objects outside the room? Explain. Answer : If we are in a dark room, then it is not possible for us to see objects in the … Read more
Exercise : Solutions of Questions on Page Number : 197 Q1 : Which of the following cannot be charged easily by friction? (a) A plastic scale (b) A copper rod (c) An inflated balloon (d) A woollen cloth Answer : (b) A copper rod Only non-conducting materials can be easily charged by friction. Copper is … Read more
Exercise : Solutions of Questions on Page Number : 180 Q1 :Fill in the blanks. (a) Most liquids that conduct electricity are solutions of ________, _______ and ________. (b) The passage of an electric current through a solution causes _________ effects. (c) If you pass current through copper sulphate solution, copper gets deposited on the … Read more
Exercise : Solutions of Questions on Page Number : 168 Q1 :Choose the correct answer. Sound can travel through (a) gases only (b) solids only (c) liquids only (d) solids, liquids and gases. Answer : (d) Sound can travel through solids, liquids, and gases. Sound requires a medium to travel through. Solid, liquid and gas … Read more
Exercise : Solutions of Questions on Page Number : 155 Q1 : Fill in the blanks. (a) Friction opposes the ________between the surfaces in contact with each other. (b) Friction depends on the _________of surfaces. (c) Friction produces _________. (d) Sprinkling of powder on the carrom board ________friction. (e) Sliding friction is ________than the static … Read more
Exercise : Solutions of Questions on Page Number : 142 Q1 : Give two examples each of situations in which you push or pull to change the state of motion of objects. Answer : Two examples of push force are as follows: (i) A heavy box at rest is pushed to move it from one … Read more
Exercise : Solutions of Questions on Page Number : 124 Q1 : What is the term used for secretions of endocrine glands responsible for changes taking place in the body? Answer : Hormones are chemical substances which are secreted by endocrine glands. They are responsible for changes taking place in the body. Q2 : Define … Read more
Exercise : Solutions of Questions on Page Number : 110 Q1 : Explain the importance of reproduction in organisms. Answer : Reproduction is a biological process through which living organisms produce offspring similar to themselves. Living organisms reproduce to maintain their number and for the continuation of their species. Thus, reproduction ensures the continuation of … Read more