hi.......... i am unable to apply the concept of mechanics but i know how to derive the equations then for this what can i do?

Dear vaibhav

It is due to lack of practice .you should practice more .

first you should see solved example and try to learn its application .then solve excersice problem and previous IIT JEE problems,

Refer H C Verma concept of physics part 1,first see solver exersice and solve unsolved excersice,You can also refer TMH ,In TMH you can get lot of solved problem.

for the concept of mechanics u shoul be very clear with the concepts of vector . once you r over with through out concepts of vector then you will be able to solve each and every question of mechanics ..