Hello

Candidates who have completed their BSc degree can apply for IIT JAM. The common eligibility for IIT JAM is: -

IIT JAM 2020 is open to all nationals (Indian/Foreign).

There is no age restriction. i.e. there is no IIT JAM Age Eligibility, regardless of your current age you can apply for JAM.

The candidates who have either appeared or are due to appear in the final examination of their qualifying degree in 2020 are also eligible to appear in the test.

IIT JAM conduct in seven subjects: -

• Physics
• Chemistry
• Mathematics
• Mathematical Statistics
• Biological Science
• Biotechnology
• Geology

And all the subjects have different eligibility criteria also. So If you want to prepare for IIT JAM Exam then you must also check the subject wise IIT JAM Eligibility Criteria here.

Below, i have mentioned the criteria for IIT JAM Physics because you have completed your BSc in Physics. If you want to apply for other subject then go to the above link.

For MSc Physics, you must have a Physics for at least two years/four semesters and Mathematics for a least one year/two semesters in your Bachelor's degree.

For Joint M.Sc.-Ph.D. in Physics and M.Sc.-Ph.D. Dual Degree in Physics, you must have Physics for at least two years/four semesters and Mathematics for a least one year/two semesters in your Bachelor's degree.

yes you are elligible . if you have done your honour from physics or studied physics for two years or four semesters in your college then you are elligible for IIT JAM . you can be also elligible for iit jam maths or chemistry paper also. you just need to have 5.5 cgpa or equivalent percentage 

check out this also 

https://university.careers360.com/articles/jam-eligibility-criteria

best wishes