Without doubt physical look is the first impression in PI but you need to be cautioned that MBA admission selection panel is looking forward to you for your positive body language and the way you greet them supported by warm handshake.
Physical look over here is meant by positivity and the warmth which you exhibit through your body language without gender bias.
You need to be well groomed both with dress wise and thought wise. The more you are with positive attitude the chances are high that you would be able to give perfect impression before you settle for PI.
Now you need to carry forward with impression and positivity with your presence of mind and natural responses supported by suave gestures.