P R E F A C E
This textbook of Science for Class X is a continuation of our attempt in the Class IX
Science textbook to comply with the guidelines of the National Curriculum
Framework-2005. We had to work within a limited time frame and also had our own
constraints coming in the way of this radical change. The revised and re-structured
syllabus for Class X covers selected topics in the broad themes of — Materials,
The World of the Living, How Things Work, Natural Phenomena and Natural Resources.
We have interpreted the syllabus to present a coherent coverage of scientific concepts
related to our daily life on the select topics. It is an integrated approach to science at
this level, with no sharp divisions into disciplines such as Physics, Chemistry, Biology
and Environmental Science.
There has been a conscious attempt to address the relevant social concerns in this
science textbook wherever possible — the concerns for people with special needs, the
issues of gender discrimination, energy and environment have found their natural
place in this book. Students have been encouraged to get into the debates on some of
the management concerns (for sustainable development, for example) so that they
can arrive at their own decisions after a scientific analysis of all the facts.
This book has some features which are meant to enhance its effectiveness. The
theme of each chapter has been introduced with examples from daily life, and if possible,
by a relevant activity that the students have to perform. The entire approach of the
book is, in fact, activity-based, i.e., the students are required to construct knowledge
themselves from these activities. The emphasis is not on definitions and technical
terms, but on the concepts involved. Special care has been taken so that the rigour of
science is not lost while simplifying the language. Difficult and challenging ideas,
which are not to be covered at this stage, have often been placed as extra material in
the boxes in light orange. The excitement of doing science comes from pursuing the
unknown — the students would have the opportunity to think and explore somewhat
beyond the syllabus and may feel the urge to continue their scientific expedition at
higher levels. All such box items, including brief biography of scientists, are, of course,
non-evaluative.
Solved examples are provided, wherever felt necessary, to clarify a concept. The
in-text questions after a main section are for the students to check their understanding
of the topic. At the end of each chapter, there is a quick review of the important points
covered in the chapter. We have introduced some multiple choice questions in the
exercises. There are problems of different difficulty levels answers to the multiple-
choice questions and numericals, and hints for the difficult questions are included at
the end of the book.
Rationalised 2023-24
