Yes, you can get a seat in Physics Hons. in Ravenshaw University.  But may take a 2nd or 3rd list for your name to appear. 

Though they have changed the admission process, with an 80% in your CBSE board exams, it won't be hard for you to earn a seat.

The only chances you won't be getting a seat is if this year's average 12th marks have risen higher or none of the first list students are leaving Ravenshaw for other opportunities.