Senior Secondary Course PHYSICS (312) 1 Course Coordinator Dr. Alok Kumar Gupta NATIONAL INSTITUTE OF OPEN SCHOOLING (An autonomous organisation under MHRD, Govt. of India) A-24-25, Institutional Area, Sector-62, NOIDA-201309 (U.P.) Website: www.nios.ac.in, Toll Free No. 18001809393 ADVISORY COMMITTEE Dr. Sitansu S. Jena Dr. Kuldeep Agarwal Dr. Rachna Bhatia Chairman Director (Academic) Assistant Director (Academic) NIOS, NOIDA (UP) NIOS, NOIDA (UP) NIOS, NOIDA (UP) CURRICULUM COMMITTEE CHAIRMAN Prof. C. K. Ghosh Director, National Centre for Innovations in Distance Education (NCIDE) IGNOU, Delhi MEMBER Sri Puran Chand Prof. B. K. Sharma Sri R. P. Sharma Sri Kanhaiya Lal Joint Secretary, COBSE Retd Professor (Physics), Education Officer (Retd.), Principal (Retd) New Delhi-110034 DESM, NCERT, New Delhi CBSE, New Delhi-110002 Dir. of Education Former Joint Commissioner, Delhi KVS Dr. P. K. Mukherjee Late Sri Sher Singh Sri Jayavir Singh Dr. K. B. Thapa Associate Professor (Physics) Principal, PGT (Physics) Assistant Professor, UIET, Desh Bandhu College, Navyug School, Lodhi Road Holy Cross School, CSJM University, Kanpur New Delhi Delhi-110003 Najafgarh Delhi-110043 Prof. R. R. Yadav Prof. A. K. Jha Prof. V. P. Srivastava Prof. Balak Das Department of Physics, Department of Physics, Retd Professor (Physics), Department of Physics, University of Allahabad, College of Commerce DESM, NCERT, New Delhi University of Lucknow, Allahabad-211002 Patna - 800016 Lucknow - 226007 Dr. Alok Kumar Gupta Academic Officer, National Institute of Open Schooling, NOIDA LESSON WRITERS AND EDITORS Prof. C. K. Ghosh Dr. P. K. Mukherjee Late Sri Sher Singh Director, National Centre for Associate Professor (Physics) Principal, Innovations in Distance Education Desh Bandhu College, New Delhi Navyug School, Lodhi Road (NCIDE), IGNOU, Delhi Delhi-110003 Sri R. S. Dass Sri D. C. Pandey Sri Kanhaiya Lal Retd. Vice Principal Assistant Director (Retd.) Principal (Retd) BRMVB Sr. Sec. School, Dir. of Education, Delhi Dir. of Education Lajpat Nagar Delhi-110024 Delhi Prof. V. P. Srivastava Sri R.K. Choudhary Dr. Alok Kumar Gupta Retd Professor (Physics), PGT (Physics) Academic Officer, DESM, NCERT, New Delhi Navyug School, Lodhi Road, Delhi NIOS, NOIDA COURSE COORDINATOR Dr. Alok Kumar Gupta Academic Officer, (Physics) NIOS, NOIDA (U.P.) GRAPHIC ILLUSTRATORS Sri Krishna Graphics C-90, West Vinod Nagar Delhi-110092 Chairman’s Message Dear learner, As the needs of the society in general, and some groups in particular, keep on changing with time, the methods and techniques required for fulfilling those aspirations also have to be modified accordingly. Education is an instrument of change. The right type of education at right time can bring about positivity in the outlook of society, attitudinal changes to face the new/fresh challenges and the courage to face difficult situations. This can be very effectively achieved by regular periodic curriculum renewal. A static curriculum does not serve any purpose, as it does not cater to the current needs and aspirations of the individual and society. For this purpose only, educationists from all over the country come together at regular intervals to deliberate on the issues of changes needed and required. As an outcome of such deliberations, the National Curriculum Framework (NCF 2005) came out, which spells out in detail the type of education desirable/needed at various levels of education - primary, elementary, secondary or senior secondary. Keeping this framework and other national and societal concerns in mind, we have currently revised the curriculum of Physics course at Senior Secondary level, as per the Common Core Curriculum provided by National Council of Educational Research and Training (NCERT) and the Council of Boards of School Education in India (COBSE) making it current and need based. Textual material production is an integral and essential part of all NIOS programmes offered through open and distance learning system. Therefore, we have taken special care to make the learning material user friendly, interesting and attractive for you. I would like to thank all the eminent persons involved in making this material interesting and relevant to your needs. I hope you will find it appealing and absorbing. On behalf of National Institute of Open Schooling, I wish you all a bright and successful future. (Dr. S. S. Jena) Chairman, NIOS A Note From the Director Dear Learner, Welcome! The Academic Department at the National Institute of Open Schooling tries to bring you new programmes, in accordance with your needs and requirements. After making a comprehensive study, we found that our curriculum is more functional related to life situations and simple. The task now was to make it more effective and useful for you. We invited leading educationists of the country and under their guidance, we have been able to revise and update the curriculum in the subject of Physics. At the same time, we have also removed old, outdated information and added new, relevant things and tried to make the learning material attractive and appealing for you. I hope you will find the new material interesting and exciting with lots of activities to do. Any suggestions for further improvement are welcome. Let me wish you all a happy and successful future. (Dr. Kuldeep Agarwal) Director (Academic) National Institute of Open Schooling A Letter to Learner Dear Learner, Welcome to the revised Physics course of National Institute of Open Schooling (NIOS). The Physics course is now divided into eight modules comprising thirty lessons on different themes. These eight modules contain predominantly the subject matter of mechanics, electricity, light and other areas of physics and represent the base knowledge which is required to progress into more advanced areas for developing appreciation for the fact that physics plays a significant role in most situations. The module VIII contains application oriented specific fields like semiconductors, electronics and communication. The Physics course has three parts. Parts 1 and 2 have theoretical part and Part 3 has laboratory work. The part 1 comprises four modules having seven lessons of module I on Motion, Force and Energy, two lessons of Module II on Mechanics of Solids and Fluids, three lessons of Module III on Thermal Physics and two lessons of Module IV on Oscillations and Waves. The second part comprises other four modules having five lessons of module V on Electricity and Magnetism, four lessons of module VI on Optics and Optical Instruments, four lessons of module VII on Atoms and Nuclei and three lessons of module VIII on Semiconductor Devices and Communication. To reduce content load at the Public Examination (PE), it has been decided that Units, Dimensions and Vectors, Motion in a Straight Line, Motion in a Plane, Gravitation, Motion of a Rigid Body, Elastic Properties of Solids, Kinetic Theory of Gases, Heat Transfer and Solar Energy, Simple Harmonic Motion, Reflection and Refraction of Light, Optical Instruments and Communication Systems which are some of the fundamental chapters in Senior Secondary Physics are for assessment through Tutor Marked Assignments (TMA) and rest lessons up to module VIII are for assessment through Public Examination (PE). We hope that you will find this learning material not only useful but also helpful in becoming a rational human being who is capable of making a positive difference in the society. Hope this new self learning material will take you to a new era of Physics. For any kind of difficulties and queries about the course, feel comfortable to write to us. Your feedback would be appreciated. We also welcome comments and suggestions which will help us to revise and improve the self learning material of Physics. We hope you will enjoy the course and find it interesting. Set the Target and Hit the Target !!! Wish you all the success, (Dr. Alok Kumar Gupta) Course Coordinator, Physics E-mail: [email protected] How to use the Study Material Your learning material has been developed by a team of physics experts in open and distance learning. A consistent format has been developed for self-study. The following points will give you an idea on how to make best use of the print material. Title is an advance organisor and conveys an idea about the contents of the lesson. Reflect on it. Introduction highlights the contents of the lesson and correlates it with your prior knowledge as well as the natural phenomena in operation in our immediate environment. Read it thoroughly. Objectives relate the contents to your desired achievements after you have learnt the lesson. Remember these. Content of the lesson has been divided into sections and sub-sections depending on thematic unity of concepts. Read the text carefully and make notes on the side margin of the page. After completing each section, answer intext questions and solve numerical problems yourself. This will give you an opportunity to check your understanding. You should continue reading a section till such time that you gain mastery over it. At some places you will find some text in italics and bold. This indicates that it is important. You must learn them. Solved Examples will help you to understand the concepts and fix your ideas. In fact, problem solving is an integral part of training in physics. Do them yourself and note the main concept being taught through a particular example. Activities are simple experiments which you can perform at your home or work place using readily available (low cost) materials. These will help you to understand physics by doing. Do them yourself and correlate your findings with your observations. Intext questions are based on the concepts discussed in every section. Answer these questions yourself in the space given below the question and then check your answers with the model answers given at the end of the lesson. This will help you to judge your progress. If you are not satisfied with the quality and authenticity of your answers, turn the pages back and study the section again.