Abandon NCERT Physics text books for Plus 2

I am a retired Physics Professor (?) of an affiliated college under University of Kerala and lecturer for many years in graduate classes and erstwhile pre-degree course and still keep some interest in the subject physics. I had already shaped half a dozen First Ranks in B Sc Physics (main) of University of Kerala and hence I believe that I have a few credentials to speak about Physics. My present apprehension is about the prescription of NCERT text books for plus two classes in State Higher Secondary and CBSE schools. The present form of NCERT text books in Physcis would certainly bring hatred among students towards the much lively subject-the physics. Presumably the writers of the present text have no class room experience otherwise they have not presented the subject matter in form of ‘water flood’. What the students get from these text books is little and that is why most teachers use credible text books instead of referring the NCET text book waste. The teachers ask students to buy NCERT books and never refer to these books while teaching. The teachers have little time to squander by reading all the rubbish in the NCERT books. I sincerely believe those writers of the text book never had been so if they had been asked to follow these text books in their school classes. Though the NCERT claim that their text books are written in conformity international standards, the presentation in foreign books are not so dreary.

The NCERT text book committee may also claim that their books would generate independent thinking among students. This sort of argument is applicable to elite classes. How can a low profile student from a poor family, unable to spell his name correctly in English even in Plus 2, without knowing the basics of Physics, think independently about new rules and ideas in Physics? The government should, therefore, reduce its control on what text book to be followed in schools and teachers and students should be given freedom in following text books.

My suggestion to the Union Human Resource Development Ministry is, ask NCERT to prescribe syllabus and not to write text books or rather compel students community to follow their text books. They can of course supply sample question paper packets and answers to students to augment their studies. The NCERT could, of course, recommend any other suitable text books to school children and if the contents are found to be prejudicial to the integrity of India or the security of the state, the books can be withdrawn. Though the present NCERT text book in Physics does not defame any community, it invites hatred to the subject Physics. Let the students learn Physics pleasantly and lively.

K A Solaman

Moment of inertia tensor is symmetric.

Moment of inertia tensor is symmetric. Why?
Ans: In linear algebra, a symmetric matrix is a square matrix A, that is equal to its transpose
i.e., A=AT
The entries of a symmetric matrix are symmetric with respect to the main diagonal (top left to bottom right). So if the entries are written as A = (aij), then aij =aji for all indices i and j. The moment of inertia tensor satisfies this condition and hence it is symmetric. (Need more details?)

K A Solaman