From 2010 Bangladesh has started to organize National Physics Olympiad (NPhO) and send team to the International Physics Olympiad. If you are interested to take part in this activity and love physics in general the first thing that you should do is to join the facebook group for the preparation of Bangladesh NPhO -- http://www.facebook.com/groups/234638419904083
We'll try to answer your questions regarding physics in the Physics sub-forum of BdMO forum -- http://matholympiad.org.bd/forum/viewforum.php?f=30
Meanwhile, you can read an interesting note by an NPhO Chamion Emroz Khan (BUET, EEE). The link to that post is: http://tarikmoon.com/bangladesh-physics-olympiad-preparation/
You can ask us questions about anything related to this by joining the facebook group or the BdMO forum.