Question

what is tecnolothon ??how can we prepare for thos exam?

Answer 1

Technothlon is an international school championship organized by the students of IIT Guwahati

by studying hard
there are exams for those

Answer 2

Some exams are meant to judge how much you can memorize and some are meant to judge how much you can understand some specific concept. Let me tell you, Technothlon is the third type !
Preparing for technothlon by mugging some books or formulae can be a good way to pass your free time. Although these are not gonna benefit you in the exam hall in any way.Because there is something called common intelligence or common sense which can't be upgraded or degraded. 
You can be your own Einstein or Newton or Faraday or Maxwell or Rutherford.
You just have to observe the situation depicted by the question and come to an answer just by using your logical skills.
To have a feel of the sort of questions asked in Technothlon, the best you can do is that you can see the last year papers of Technothlon :