Hey.

Here is the important topics and their respective weightage  for PCM for preparation of JEE mains

Mathematics-

Co-Ordinate Geometry  17%  

Calculus  27%

 Algebra  27%

 Vector/3-D Geometry  10%

 Trigonometry  6%

 Sets & Relations,Mathematical Reasoning, Statistics  13  

Physics-

Mechanics  30%  

Heat & Thermodynamics  7%

 Electrostatics & Current Electricity  17%

 Magnetics & Electro Magnetic Induction  13%

 Optics & Waves  3%

 Modern Physics  10%

 Simple Harmonic Motion, Waves & Elasticity  7%  

Semi-Conductor Devices, Electromagnetic Waves and Principles of Communication- 13%

Chemistry-

Inorganic Chemistry- Classification of Elements and Periodicity in Properties, General Principles and Process of Isolation of Metals, Hydrogen, s - Block Elements (Alkali and Alkaline Earth Metals), Co-ordination Compounds, Environmental Chemistry to name few.  

Organic Chemistry- Purification and Characterisation of Organic Compounds, Some Basic Principles of Organic Chemistry, Hydrocarbons,Organic Compounds Containing Oxygen, Organic Compounds Containing Nitrogen, Bio Moleculesetc.  

Physical Chemistry- Some Basic concepts in Chemistry,States of Matter, Atomic Structure, Chemical Bonding and Molecular Structure,Chemical Thermodynamics, Equilibrium, Surface Chemistry,Chemical Kinetics and Redox Reactions and Electrochemistry.

 Topic-wise Percentage Break-up-

Organic Chemistry  30%

 Inorganic Chemistry  30%  

Physical Chemistry  40%  

Hello Abhishek

Important chapters of Physics that contains High Weightage are

1.Heat & Thermodynamics

2.Ray Optics

3.Electromagnetic Waves

4.Semiconductors

5.Error & Instrument Analysis

6.Gravitation

7.Wave Optics

8.Photoelectric Effect

9.Oscillations

Important chapters of Chemistry that contains High Weightage are

1.Atomic Structure

2.Gaseous & Liquid State

3.Electrochemistry

4.Chemical Kinetics

5.Nuclear & Surface Chemistry

6.Chemical Bonding

7.d-Block Elements

8.Co-ordination Compound

9.Alkyl Halides

10.Aromatic Compounds

Important chapters of Mathematics that contains High Weightage are

1.3 Dimensional Geometry

2.Vectors

3.Determinant & Matrices

4.Sequence & Series

5.Straight Line

6.Circle

7.Probability Distribution (Binomial + Mean & Variance)

If you go through this chapters thoroughly you can get good marks in JEE

Good Luck!!