Dear Aniket Sharma,

You cannot really say that a particular topic is important in IIT-JEE but here i am giving you some topics from Physics,Chemistry & Mathematics that are a little more scoring than the rest of the topics !!!

Physics:

1.Modern Physics(X-Rays,Photoelectric Effect,Atomic Physics)

2.Kinematics

3.Mechanics(Rotational Motion-More important)

4.Work,Power & Energy

5.Reflection & Refraction of Light(Optics-V.important)

Chemistry :

1.Atomic Structure

2.Properties of elements in the Periodic Table

3.Chemical Energetics

4.Rates of Chemical Reactions(Chemiical Kinetics)

5.Chemical Bonding(V.Important)

6.D & F block elements(Remember the reactions)

7.Co-ordination Chemistry

8.Organic Chemistry(Full-Highly Scoring)

9.Solutions & Thermodynamics(Scoring)

Mathematics :

1.Complex Numbers(Easy & Scoring)

2.3D Geometry(V.Easy & Highly Scoring)

3.Vectors

4.Matrices(V.Easy)

5.Circle,Parabola,Straight lines(Simple & Scoring)

6.Definite Integration(V.Easy & Scoring)

7.Probability

Hope this helped you dear....

                                                       Best Of Luck...........

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