Comprehensive CBSE Question Bank in Science IX (Term-II)

CBSE II Question Bank in Science CLASS 9 Features Short Answer Type Questions Long Answer Type Questions Strictly Based on the Latest CBSE Term-wise Syllabus Case Study Based MCQs Chapter Summary Very Short Answer Type Questions



Comprehensive CBSE Question Bank in Science Term–II (For Class IX)



Comprehensive CBSE Question Bank in Science Term–II (For Class IX) (According to the Latest CBSE Examination Pattern) By Dr. N.K. Sharma Nutan Vidya Mandir Dilshad Garden Delhi   laxmi Publications (P) Ltd (An iso 9001:2015 company) bengaluru • chennai • guwahati • hyderabad • jalandhar Kochi • kolkata • lucknow • mumbai • ranchi new delhi

Comprehensive CBSE Question Bank in Science–IX (Term-II) Copyright © by Laxmi Publications Pvt., Ltd. All rights reserved including those of translation into other languages. In accordance with the Copyright (Amendment) Act, 2012, no part of this publication may be reproduced, stored in a retrieval system, translated into any other language or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise. Any such act or scanning, uploading, and or electronic sharing of any part of this book without the permission of the publisher constitutes unlawful piracy and theft of the copyright holder’s intellectual property. If you would like to use material from the book (other than for review purposes), prior written permission must be obtained from the publishers. Printed and bound in India Typeset at : Excellent Graphics, Delhi. New Edition ISBN : 978-93-93738-06-6 Limits of Liability/Disclaimer of Warranty: The publisher and the author make no representation or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties. The advice, strategies, and activities contained herein may not be suitable for every situation. In performing activities adult supervision must be sought. Likewise, common sense and care are essential to the conduct of any and all activities, whether described in this book or otherwise. Neither the publisher nor the author shall be liable or assumes any responsibility for any injuries or damages arising here from. The fact that an organization or Website if referred to in this work as a citation and/or a potential source of further information does not mean that the author or the publisher endorses the information the organization or Website may provide or recommendations it may make. Further, readers must be aware that the Internet Websites listed in this work may have changed or disappeared between when this work was written and when it is read. All trademarks, logos or any other mark such as Vibgyor, USP, Amanda, Golden Bells, Firewall Media, Mercury, Trinity, Laxmi appearing in this work are trademarks and intellectual property owned by or licensed to Laxmi Publications, its subsidiaries or affiliates. Notwithstanding this disclaimer, all other names and marks mentioned in this work are the trade names, trademarks or service marks of their respective owners. & Bengaluru 080-26 75 69 30 & Chennai 044-24 34 47 26 Branches & Guwahati 0361-254 36 69 & Hyderabad 040-27 55 53 83 & Jalandhar 0181-222 12 72 & Kochi 0484-405 13 03 & Kolkata 033-40 04 77 79 & Lucknow 0522-430 36 13 Published in India by & Ranchi 0651-224 24 64 Laxmi Publications (P) Ltd. C—00000/021/12 Printed at : Ajit Printing Press, Delhi. (An ISO 9001:2015 Company) 113, GOLDEN HOUSE, GURUDWARA ROAD, DARYAGANJ, NEW DELHI - 110002, INDIA Telephone : 91-11-4353 2500, 4353 2501 www.laxmipublications.com [email protected]

Contents Pages Theme: Materials Unit I: Matter—It’s Nature and Behaviour 1–52 1. Atoms and Molecules (NCERT Textbook Chapter-3) 1 2. Structure of the Atom (NCERT Textbook Chapter-4) 28 Theme: The World of The Living 53–71 Unit II: Organisation in the Living World 3. Why do We Fall IIl? (NCERT Textbook Chapter-13) 53 Theme: Moving Things, People And Ideas Unit Iii: Motion, Force and Work 72–128 4. Gravitation (NCERT Textbook Chapter-10) 72 5. Work and Energy (NCERT Textbook Chapter-11) 97



Syllabus Class IX Units Evaluation Scheme Marks I Theory 18 II 08 III Term-II 14 Matter-Its Nature and Behaviour: Chapter 3 and 4 40 Organization in the Living World: Chapter -13 Motion, Force and Work: 10 and 11 Total TERM-II Theme: Materials Unit I: Matter- It’s Nature and Behaviour Chapter – 3 Atoms and Molecules Particle nature and their basic units: Atoms and molecules, Law of constant proportions, Atomic and molecular masses. Mole concept: Relationship of mole to mass of the particles and numbers. Chapter – 4 Structure of Atom Structure of atoms: Electrons, protons and neutrons, valency, chemical formula of common compounds. Isotopes and Isobars. Theme: The World of the Living Unit II: Organization in the Living World Chapter – 13 Why do we fall ill Health and Diseases: Health and its failure. Infectious and Non-infectious diseases, their causes and manifestation.Diseases caused by microbes (Virus, Bacteria and Protozoans) and their prevention; Principles of treatment and prevention. Pulse Polio programmes.

Theme: Moving Things, People and Ideas Unit III: Motion, Force and Work Chapter – 10 Gravitation Gravitation: Gravitation; Universal Law of Gravitation, Force of Gravitation of the earth (gravity), Acceleration due to Gravity; Mass and Weight; Free fall. Chapter – 11 Work and Energy Work, energy and power: Work done by a Force, Energy, power; Kinetic and Potential energy; Law of conservation of energy.

CHAPTER 2: Structure of the Atom SUMMARY OF THE CHAPTER 1. VERY SHORT ANSWER TYPE QUESTIONS (1 MARK) 28

Structure of the Atom 29

30 Science—IX   Fig. 2.1

Structure of the Atom 31 2. SHORT ANSWER TYPE-I QUESTIONS (2 MARKS) Fig. 2.2

32 Science—IX 

Structure of the Atom 33 Fig. 2.3. Bohr’s Model with Three Shells   

34 Science—IX 

Structure of the Atom 35 Fig. 2.4

36 Science—IX  Fig. 2.5 Atomic number of sodium atom = 11 Atomic number of sodium ion = 10

Structure of the Atom 37  3. SHORT ANSWER TYPE-II QUESTIONS (3 MARKS)  

48 Science—IX          5. CASE STUDIES Fig. 2.11. Cathode rays cast shadows of metal objects placed in their path

Structure of the Atom (b) cathode rays (c) -rays 49 (a) X-rays (d) anode rays (a) assertion is correct and reason is correct (b) assertion is correct but reason is wrong (c) assertion is wrong but reason is correct (d) assertion is wrong and reason is wrong (a) Cathode rays are deflected towards positive plate. (b) Cathode rays are deflected towards negative plate. (c) Cathode rays travel in a straight line. (d) Cathode rays travel in zig-zag path. Fig. 2.12. Production of positive rays in a discharge tube

50 Science—IX (a) Anode rays travel in a straight line. (b) Anode rays are material particles. (c) Anode rays are positively charged. (d) none of these (a) X-rays (b) Gamma rays (c) Cathode rays (d) none of these (a) 1827 (b) 1830 (c) 1832 (d) 1837         Fig. 2.13. Scattering of -particle by a metal (a) low malleability of gold  (c) low ductibility of gold (b) high malleability of gold (d) high ductibility of gold

Structure of the Atom 51 (a) Atomic nucleus (b) Electron (c) Proton (d) Neutron     (a) protium (b) deuterium (c) tritium (d) none of these (a) 1 (b) 3 (c) 4 (d) 7 (a) N Bohr (b) E Goldstein (c) Rutherford (d) JJ Thomson  (a) (I) and (III) (b) (II) and (III) (c) (I) and (IV) (d) Only (I) 1. (i) (d) anode rays (ii) (a) assertion is correct and reason is correct (iii) (c) Since cathode rays are negativity charged not positively. (iv) (a) Cathode rays are negatively charged, hence they are deflected towards posi- tive plate.

52 Science—IX 2. (i) (d) none of these (ii) (d) X-rays – no charge, Gamma rays – no charge, Cathode rays – negative charge (iii) (c) Goldstein (iv) (d) 1837 times the mass of the electron 3. (i) (b) high malleability of gold (ii) (a) Atomic nucleus (iii) (b) 2 positive charge and 4 mass unit (iv) (d) Because all the statements are true. 4. (i) (b) Deuterium (1H2) Number of electron (1), Number of proton (1), Number of neutron (1) (ii) (a) 1 (iii) (d) The first model of an atom was given by JJ Thomson. According to him, an atom consists or a sphere of positive charge with negatively charged elec- trons embedded in it. (iv) (a) According to Rutherford model, a central positively charged nucleus is present in the atom and electrons revolve around it. This model is similar to solar system so also called planetary model.

THEME: THE WORLD OF THE LIVING UNIT II: ORGANISATION IN THE LIVING WORLD CHAPTER 3: Why do We Fall IIl? SUMMARY OF THE CHAPTER 53

54 Science—IX 1. VERY SHORT ANSWER TYPE QUESTIONS (1 MARK)

Why do We Fall IIl? 55

56 Science—IX 2. SHORT ANSWER TYPE-I QUESTIONS (2 MARKS)

Why do We Fall IIl? 57

58 Science—IX

Why do We Fall IIl? 59 21. Are the answers to the questions 19 and 20 necessarily the same or different? Why? Ans. Answers to the questions 19 and 20 are different. Reason: (i) When we think about disease, we think about individual sufferers. But when we think about health, we think about societies and communities. (ii) It is possible to be in poor health without suffering from a particular disease. This is particularly true of social and mental health. 22. List any three reasons why you would think that you are sick and ought to see a doctor. If only one of these symptoms were present, would you still go to the doctor? Why or why not? Ans. Common symptoms which indicate sickness are: (i) Headache (ii) Cough (iii) Loose motion. Even seeing one symptom, I will go to doctor. Reason: A single symptom is the sign of a disease. On delaying it may lead to serious illness. For example, headache may mean meningitis. 23. In which of the following case do you think the long-term effects on your health are likely to be most unpleasant?  if you get jaundice, if you get lice,  if you get acne. Why? Ans. Jaundice because it is a chronic disease and takes long time to be cured. Moreover, jaundice affects the whole body and it takes long time to be healthy. 24. Why are we normally advised to take balanced and nourishing food when we are sick? Ans. Infectious diseases show a lack of success of the immune system of the body. For the functioning of immune system properly, sufficient nourishment and easily digestable food is necessary for a sick person. 25. What is immunisation? Ans. Introduction of mild type of infection (microbes) or killed infectious microbes into the body by vaccination/by other means to activate the immune system against a particular infection/disease is called immunisation. 26. A baby is not able to tell her/his caretakers that she/he is sick. What would help us to find out: (a) that the baby is sick? (b) what the sickness is? Ans. (a) The symptoms and signs can tell that the baby is sick. Symptoms may be cough, loose motions, wound with pus, vomiting, etc. (b) (i) By looking signs of disease on the basis of the symptom. Signs will give a little more definite indication of the presence of a particular disease. For example, yellow colour of eyes, skin, etc., indicate jaundice. (ii) To pinpoint the disease, further laboratory tests to be done. 27. Give two examples for each of the following: (a) Acute diseases (b) Chronic diseases (c) Infectious diseases (d) Non-infectious diseases

60 Science—IX 3. SHORT ANSWER TYPE-II QUESTIONS (3 MARKS)

Why do We Fall IIl? 61

62 Science—IX

68 Science—IX 5. CASE STUDIES

Why do We Fall IIl? 69 (a) Influenza (b) Dengue fever (c) AIDS (d) none of these (a) If you get jaundice (b) If you get lice (c) If you get acne (d) If you get cold (a) Congential diseases (b) Pandemic diseases (c) Non-infections diseases (d) Infectious diseases (a) These are transferred from a patient to the healthy person. (b) These are not caused by a pathogens. (c) These are not caused by nutritional deficiency. (d) none of these (a) Maleria (b) Jaundice (c) Flue (d) All of these

70 Science—IX Fig. 3.1. Common methods of transmission of diseases (a) malaria (b) kala-azar (c) elephantasis (d) none of these (a) Preventing overcrowding (b) Providing safe drinking water (c) Use of clean toilets (d) All of these

Why do We Fall IIl? 71 (a) a worm (b) bacteria (c) virus (d) protozoan 1. (i) (d) All the given diseases are caused by viruses. (ii) (a) Because jaundice is a chronic disease and takes long time to be cured and affects the whole body and takes long time to be healthy. (iii) (c) Non-infectious diseases (iv) (b) Infectious diseases are caused by a pathogens (disease causing organism). 2. (i) (d) All the given diseases are caused by parastic organisms. (ii) (b) All the given observations indicate symptoms of a disease. (iii) (d) All the given ways prevents infectious diseases. (iv) (a) Cholera 3. (i) (d) none of these (ii) (d) All given precautions reduce the incidence of infectious diseases. (iii) (d) All the given statements are correct. (iv) (c) AID is caused by the human immunodeficiency (HIV) virus.

ISBN: 978-93-93738-06-6 789393 738066 T09-8684-179-COMP.CBSE QB SCIENC T-II IX