I am preparing for jee 2015 . I am a bit weak in relative motion and projectile motion on inclined plane . What should i do to master these two . I am strong in all other fields

from my point of viw you shoul see the online books of relative motion and projectile motion...

Thnik in practical way to solve the problems ,That is relative motion for (va-vb),use ncert material for imaginary analysis,and H.C.varma concepts of physics for problem solving

You should prepare for projectile motion. Because it is important chapter then the inclined plane.