Science (Theory) Class IX

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1 Science (Theory) Class IX Time Allowed 2½ hours General instructions: Maximum Marks: The question paper comprises of two Sections A and B. You have to attempt both the sections. 2. All questions are compulsory. 3. All questions in section A and all questions in section B are to be attempted separately. 4. Question numbers 1 to 6 in section A and 17 to 19 in section B are short answer type questions and carry one mark each. 5. Question numbers 7 to 10 in section A and 20 to 24 in section B are short answer type questions and carry two marks each. 6. Question numbers 11 to 14 in section A and 25 to 26 in section B are short answer type questions and carry three marks each. 7. Question number 15 to 16 in section A and 27 in section B are long answer type questions and carry five marks each. Section A Q1. Light and sound are not considered to be matter. Why? Q 2. Which separation technique will you apply for the separation of the following? a. Sodium chloride from its solution in water. b. Oil from water. (1/2 mark * 2 = 1 Q 3. In which direction do the buoyant force and weight act on an object, immersed in a liquid? Q 4. Define one atomic mass unit. Q 5. What is power? Define 1 watt. Q 6. Why are sound waves called longitudinal waves? Q 7. Give two properties of colloids. Q 8. Define work. State its SI unit. When is work done negative? (1 (1 (1*2 mark = 2 marks) (2 marks) Q 9. Give reasons: a. Naphthalene balls disappear with time without leaving any solid. b. We can get the smell of perfume sitting several metres away. (2*1 mark = 2 marks)

Q 10. Differentiate between vector and scalar quantities. Give examples of each. (2 marks) Q 11. Which of the following waves has the most pitch, the most loudness?

2 Q 10. Differentiate between vector and scalar quantities. Give examples of each. (2 marks) Q 11. Which of the following waves has the most pitch, the most loudness? State one more characteristic of sound waves. (3 marks) 1) 2) 3) 4) Q 12. Derive the equation for position-time graphically. A car starting from rest moves with a uniform acceleration of 0.1m/s 2 for 2 minutes. Find the distance traveled. (3 marks) Q 13. Write the formula of the following compounds: (1*3 mark = 3 marks) a. Aluminium chloride b. Magnesium sulphate c. Potassium nitrate Q 14. How does the force of gravitation between two objects change if i) Distance between them is halved ii) Mass of each object is doubled iii) The objects are taken to the moon where acceleration due to gravity is 1/6 th its value on the earth. (3 marks) Q 15. An atom X has 11 electrons, 11 protons and 12 neutrons. Calculate the following: a. Atomic number b. Mass number c. Electronic configuration of the atom d. Number of valence electrons e. Valency (5 * 1 mark = 5 marks) Q 16. State Newton s third law of motion. Define a force of 1 newton. Obtain Newton s first law of motion from Newton s second law of motion. (5 marks) Section B Q 17. Define nomenclature. Q 18. Name any two diseases that are transmitted through air.

3 Q 19. Plasma membrane is called a selectively permeable membrane. Explain why? Q 20. What are collenchyma tissues? Q 21. What are sponges? (2 marks) (2 marks) Q22. Explain the basic principle of immunization. (2 marks) Q 23. Give the differences between acute and chronic diseases. Q 24. Give four characteristics of epithelial tissue. (2marks) (2 marks) Q 25. Explain the term mixed cropping and intercropping. Mention one advantage of each. (3 marks) Q 26. Explain the characteristic features of kingdom monera giving suitable examples. (3 marks) Q 27. Differentiate between plant and animal cells with help of a labeled diagram. (5 marks)

4 Answers Section A Ans 1. Light and sound are not considered to be matter because they do not occupy space and have no mass. Ans 2. a. Evaporation (1/2 b. Separating funnel technique (1/2 Ans 3. Buoyant force acts in the upward direction and weight acts in down ward direction. (1 Ans 4. One atomic mass unit is a mass unit equal to exactly one twelfth (1/12 th ) the mass of one atom of carbon -12. (1 Ans 5. Power is rate of doing work. (1/2 1 watt = 1 joule per second. If 1 joule of work is done in 1 second, the rate of doing work or power is 1 watt. (1/2 Ans 6. They are longitudinal as the vibrations of the particles of the medium are in the direction of propagation of the wave. Ans 7. Two properties of colloids are: a. A colloid is a heterogeneous mixture. ( 1 b. A colloid is quite stable i.e. the particles of a colloid do not settle down when left undisturbed. ( 1 Ans 8. Work is done when a force acts on an object and it moves in the direction of the applied force. ( 1 SI unit of work is joule. (1/2 Work done is negative when force acts opposite to the direction of displacement. (1/2 Ans 9. a. This is because naphthalene balls absorb energy from the surrounding and undergoes sublimation and get converted to gaseous phase. ( 1 b. This is because the molecules of perfume enter in air and diffuse in all the directions. (1

Ans 10.Vector quantities have both magnitude and direction. Scalar quantities have only magnitude. ( 1 Example of vector is acceleration and of scalar is mass. ( 1 Ans 11.

5 Ans 10.Vector quantities have both magnitude and direction. Scalar quantities have only magnitude. ( 1 Example of vector is acceleration and of scalar is mass. ( 1 Ans 11. Wave 4 has the highest frequency so it has maximum pitch, wave 3 has the highest amplitude so it has the most loudness. One more characteristic of sound is quality or timbre. (3 marks) Ans 12. In time t the velocity of the body increases from u to v. The area under the graph is the distance covered by the object. S = area OABC = area of rectangle OADC+ area of triangle ABD = u x t + ½(t x at) = ut + ½ at 2 (2marks) According to the question u = 0, a = 0.1m/s 2, t= 120s S = ut + ½ at 2 = 0 + ½(0.1)(120) 2 = 720 m ( 1 Ans 13. a.

6 b. c. Ans 14. If distance is halved force will be 4 times. If mass of each object is doubled, the force will be 4 times. No change in the force between the objects. Note that here we are not finding the force between the object and the earth or the moon. Ans15. a. Atomic number = Z = Number of protons = 11 b. Mass number = A = Number of protons + Number of neutrons = = 23 c. Electronic configuration of the atom X = K L M d. Number of valence electrons = Number of electrons in the outermost shell = 1 e. Valency = 1 (5 * 1 mark = 5 marks) Ans 16. Newton s second law of motion states that the rate of change of momentum of an object is proportional to the applied unbalanced force. This change is in the direction of the applied force. ( 2marks) A force of 1 Newton is defined as the force that produces an acceleration of 1 mss when it acts on an object of 1kg mass. According to Newton s second law F = ma F = m (v-u)/t

7 If force is zero then v-u=0 or v=u. This means that the velocity of object will not change if force acting on it is zero. This is Newton s first law. (2marks) Section B Ans 17. Nomenclature is the process of assigning unique names to living organisms on the basis of rules framed by scientists. Ans 18. Pneumonia and Tuberculosis Ans 19. Plasma membrane is the outer covering of the cell that separates the contents of the cell from its external environment. It allows or permits the entry and exit of some materials in and out of the cell. It also prevents movement of some other materials. Ans 20. Collenchyma is a kind of simple permanent tissue found in plants. (1/2 The cells of this tissue are living, elongated, and irregularly thickened at the corners.(1/2 It provides flexibility in plants so as to allow easy bending in various parts without breaking. (1/2 It also provides mechanical support to the plant. (1/2 Ans 21. The sponges are animals of the phylum Porifera. They are primitive, sessile, mostly marine, filter feeders that pump water through their bodies to filter out particles of food matter. (1 Sponges represent the simplest of animals. They are the pore-bearing animals that have spongocoel and canal system. Sycon, Spongilla, and Euplectelea are some examples. Ans 22. Immunization is the process of creating immunity or protection against a specific disease. When the immune system first sees an infectious microbe, it responds against it and then remembers it specifically. So the next time that particular microbe enters the body, immune system responds with even greater vigor. This eliminates the infection even more quickly than the first time. During immunization we fool the immune system into developing a memory for a particular infection by injecting something that mimics the microbes. Ans 23. Acute diseases 1. Its duration is very short. For example common cold. 2. It is generally not associated with feeling of tiredness, and weight Chronic diseases It lasts for longer period, as much as lifetime. For example elephantiasis. It is mostly associated with feeling of

8 loss. 3. Since it gets over very soon, it does not get time to cause major effects on general health. tiredness, and weight loss. It causes prolonged general poor health. (Any two) )2 * 1 mark -= 2 marks) Ans 24. The four characteristics of epithelial cells are: 1. These cells are packed tightly with each other and form a continuous sheet. (1/2 2. The material that joins them to each other, that is the cementing material, is very less. (1/2 3. Intercellular spaces are negligible. (1/2 4. There is a basement membrane that is extra cellular and fibrous on which the epithelium rests. (1/2 Ans 25. Mixed cropping is the practice of growing two or more crops simultaneously on the same piece of land. For example, wheat grown with gram or wheat with grown mustard. (1 Advantage: It minimizes the risk of crop failure due to lack of rainfall. (1/2 In intercropping, two or more crops are grown on the same field in a definite pattern. The crops are selected such that their nutrient requirements are different. Advantages: 1. It ensures maximum utilization of the supplied nutrients. 2. It also prevents spreading of pests and diseases. 3. It helps in maintaining the soil fertility. ( Any one) (1/2 Ans 26. Monera are the simplest of all living organisms. They do not have a well defined nucleus or organelles. Some of them have a cell wall while others do not. They could either be autotrophic i.e. synthesize their own food or heterotrophic that obtains its food from the environment. The kingdom Monera is divided into sub kingdoms: 1. Archaebacteria also called primitive bacteria, and 2. Eubacteria also called true bacteria Archaebacteria are autotrophs, and although they do not photosynthesize they derive energy from chemical sources such as ammonia, methane, hydrogen sulphide e.t.c. For example

archae thrive in dead sea, marshy areas e.t.c. Eubacteria are prokaryotic cells, often with a cell wall and can be autotrophic, or saprophytic or parasitic. Some of examples of Kingdom Monera are: 1.

9 archae thrive in dead sea, marshy areas e.t.c. Eubacteria are prokaryotic cells, often with a cell wall and can be autotrophic, or saprophytic or parasitic. Some of examples of Kingdom Monera are: 1. Blue-green algae or cyanobacteria. and 2. Mycoplasma. Ans 27. Following are the differences between a plant and animal cell. 1. Plant cells have a cell wall surrounding the cell membrane, which is absent in animal cells. (1/2 2. Plastids such as chloroplasts are present only in plant cells. (1/2 3. Barrel shaped organelle called centriole is found only in animal cells. (1/2 4. Vacuoles are small sized in animal cells, while plant cells have very large vacuoles. (1/2 (3 marks)

SCIENCE (IX) SECTION A-PHYSICS

SCIENCE (IX) SECTION A-PHYSICS SCIENCE (IX) SAMPLE PAPER SECTION A-PHYSICS 1. A body is moving with a uniform speed of 5 m/s. Calculate the amount of force acting on it. 2. Is it possible for an object to have zero velocity but still