My friend recently gave his MTech interview at IIT Patna and aced it. The entire process lasted for 46 minutes. His interview was conducted by a panel of 6 members.
The panelists welcomes him and after the introduction, they went through his BTech mark sheet to see the branch and subjects he had graduated with. The interview soon began and they probed him with basic questions related to mathematics, SOM, and 12th-class physics. They even asked him to explain some answers in detail on the whiteboard.
Overall, they were very satisfied with his answers and he managed to get selected!