There are no payment seats at IIT's for MSc Physics. You have qualify the IIT JAM with good ranks in order to get admissions in course like:

• MSc
• Joint MSc-PhD
• Dual MSc-PhD
• Integrated MSc-PhD

Now in the time of counselling you have to pay Rs.10,000 if you are a general student in order to book a seat and Rs.5000 for SC/ST.

The fees per semester varies from Rs. 25,000-50,000/sem depending on the IIT you are get admitted in.

To know more about IIT JAM counselling you may visit the link below:

https://university.careers360.com/articles/jam-counselling

To know more about IIT JAM visit the link below:

https://university.careers360.com/articles/jam-syllabus

I hope my answer helps. All the very best for your future endeavors!