Hello aspirant,

It is not fixed that how much part in neet paper will come from ncert books but ncert curriculum is like a Bible for neet aspirants as it contains very good proportion of questions asked in neet exam.

According to the question papers from the previous year, 15 to 20 percent of all the questions in physics are taken directly from the NCERT books, and another 15 to 20 percent are based on the NCERT curriculum.

Thank you

Hope this information helps you.