CBSE ADDA

Q. What is luster? Ans: Materials around us have a particular type of shine called Luster like gold, silver, aluminum etc Q. Some metal can hammered into thin sheet without breaking into pieces. Name this property of metals? Ans: Malleability. Q. Some metal drawn into thin wire. Name this property of metals?  Ans: Ductility. Q. Name material used to make chalk?  Ans: Calcium carbonate Q. Why do houses have cement floor?  Ans: Houses have cement floor because it can polished to make attractive. Q. Define soluble and insoluble substance? Ans: Material that mixed with water is called soluble e.g. acid, base, milk, lemon juice, sugar and alcohol. Material that do not mixed with water is called insoluble like oil, sand, alum etc  Q. what will happen if you drop piece of chalk and sponge in to glass of water? Ans: Chalk and sponge absorb water due to gap between their particles. Q. Which material you prefer to use for furniture? Ans: Wood and Metal  as

9 th   physics:  Force and laws of Motion 1. An object of mass 2 kg is sliding with a constant velocity of 4 m/ s   on a frictionless horizontal table. The force required to keep the object moving with the same velocity is (a) 32 N               (b) 0 N                (c) 2 N                 (d) 8 N                  Ans: (b]        2. Rocket works on the principle of conservation of (a) mass              (b)energy            (c) momentum    (d) velocity          Ans:  [c] 3.A car is moving at 45 km/hr.A constant force acts on the car for 10 sc .So that it's velocity becomes 63 km/hr .The distance travelled by car during this interval of 10 sec is : a) 100 m         b) 150 m              c) 200 m        d) 50 m                       Ans:  [b]      4. What is the definition of balanced and unbalanced force? Ans:   When two equal forces acting on an object in opposite directions called balanced force.   When something does not move the forc

JSUNIL'S X maths Chapter: 02 Polynomials Test paper :

CLASS VII  Science (Physics)  Chapter- Heat and Temperature  Question with solution Part-1  Q.1. What is heat? Ans: Heat is form of energy that produces feeling of hotness. It is measured in Joule . Calorie is used to measure energy value of food. 1 cal. =4.2 joule Q. 2.What is energy? Ans: Energy is capacity to do work. Energy is neither created nor destroyed it can only changed one form to another. Q. 3.What are the effects of heat? Ans: Heat cause many change in living and non living thing. They are 1. Heat increase in temperature  2. Heat expand a substance    3. Heat changes the state    4. Heat bring chemical change 5.Heat effect living thing Q.4. What is temperature? Ans: The degree of hotness and coldness of a body is called temperature of body. Thermometer is an instrument used to measure temperature. It is work on principle of expansion