General Science For Upsc

• Shabnam Johry • Tara Chand ( Coordinator) • Tanushri Saxena • Renu Kathpalia McGraw Hill Education (India) Private Limited NEW DELHI McGraw Hill Education Offices New Delhi New York St Louis San Francisco Auckland Bogotá Caracas Kuala Lumpur Lisbon London Madrid Mexico City Milan Montreal San Juan Santiago Singapore Sydney Tokyo Toronto Published by McGraw Hill Education (India) Private Limited, P-24, Green Park Extension, New Delhi 110 016. General Science: For Civil Services Preliminary Examination—Paper I, 2e Copyright © 2014, 2013, McGraw Hill Education (India) Private Limited. No part of this publication may be reproduced or distributed in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise or stored in a database or retrieval system without the prior written permission of the publishers. The program listings (if any) may be entered, stored and executed in a computer system, but they may not be reproduced for publication. This edition can be exported from India only by the publishers, McGraw Hill Education (India) Private Limited. Print Edition ISBN (13): 978-93-513-4353-0 ISBN (10): 93-513-4353-7 E-book Edition ISBN (13): 978-93-392-1391-6 ISBN (10): 93-392-1391-2 Managing Director: Kaushik Bellani Deputy General Manager—Test Prep and School: Tanmoy Roychowdhury Publishing Manager—Test Prep: K N Prakash Assistant Sponsoring Editor—Bhavna Malhotra Asst Manager (Developmental Editing): Anubha Srivastava Asst Manager—Production: Medha Arora Senior Production Executive: Dharmender Sharma Product Specialist: Vikas Sharma General Manager—Production: Rajender P. Ghansela Manager—Production: Reji Kumar Information contained in this work has been obtained by McGraw Hill Education (India), from sources believed to be reliable. However, neither McGraw Hill Education (India) nor its authors guarantee the accuracy or completeness of any information published herein, and neither McGraw Hill Education (India) nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that McGraw Hill Education (India) and its authors are supplying information but are not attempting to render engineering or other professional services. If such services are required, the assistance of an appropriate professional should be sought. Typeset at Script Makers, 19, A1-B, DDA Market, Paschim Vihar, New Delhi 110063 and text and cover printed at Cover Designer: K. Anoop ABOUT THE AUTHORS Dr Tara Chand A former Dean of St Stephen’s College, University of Delhi, Dr Tara Chand taught Physics in that college for over 36 years. He did his B.Sc (Hons), M.Sc and Ph.D from the University of Delhi and his post-doctoral research at the renowned Fermilab, Chicago, USA. Dr Tara Chand has been the overall coordinator of McGraw Hill’s bestselling manual General Studies: Paper I for Civil Services Preliminary Examination since its inception in 1985. He has also contributed the Physics portion in the manual. He closely follows the recent trends in the pattern of the General Studies Paper. Dr Shabnam Johry D Shabnam Johry is an Associate Professor of Chemistry at St. Stephen’s College, University of Delhi. She holds a Ph.D. in Organic Chemistry from the University of Delhi. Dr Johry enjoys the honour of being the first lady student of St. Stephen’s College to join the faculty of this esteemed institution, and has a teaching experience of over 30 years in this college. Dr Tanushri Saxena D Tanushri Saxena is an Associate Professor of Zoology in Swami Shraddhanand College of the University of Delhi where she has been teaching for the past 20 years. She received her bachelor’s and master’s and PhD degrees from the University of Delhi. She is a member of Indian Society of General and Comparative Endocrinology a