Taruna ;

As JEE mains 2020 is going to be conducted in the format of 300 marks. Physics, chemistry and mathematics each of 100 marks. Starting with physics;

• Physics and measurement
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• Rotational motion
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• Thermodynamics
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• Kinematics
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• Work, energy and power
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• Properties of solids and liquids
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• Gravitation
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• Laws of motion
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• Oscillations and waves
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• Electronic devices
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• Kinetic theory of gases
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• Current electricity
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• Communication systems
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• Electromagnetic induction and alternating currents
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• Magnetic effects of current and magnetism
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• Optics
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• Electromagnetic waves
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• Atoms and nuclei
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• Electrostatics
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• Dual nature of matter and radiation
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These are the chapters that'll come from physics probably with more questions from rotation and electrostatics.

For chemistry; you should take the whole NCERT seriously. Most of the questions in chemistry last year came directly from the NCERT book. So, you must study the whole 2 years course properly.

Speaking of chapters;

Physical Chemistry

• Some basic concepts in chemistry
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• States of matter
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• Atomic structure
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• Chemical bonding and molecular structure
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• Chemical thermodynamics
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• Solutions
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• Equilibrium
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• Redox reactions and electrochemistry
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• Chemical kinetics
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• Surface chemistry
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Organic Chemistry

• Purification and characterisation of organic compounds
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• Hydrocarbons
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• Chemistry in everyday life
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• Principles related to practical chemistry
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• Organic compounds containing halogens
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• Organic compounds containing oxygen
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• Organic compounds containing nitrogen
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• Polymers
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• Some basic principles of organic chemistry
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• Biomolecules
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Inorganic Chemistry

• Classification of elements and periodicity in properties
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• Hydrogen
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• Block elements (alkali and alkaline earth metals)
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• P Block elements group 13 to group 18 elements
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• d- and f - block elements
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• Co-ordination compounds
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• Environmental chemistry
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• General principles and processes of isolation of metals
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You must read every portion seriously as some times very very easy questions may come from the chapters that you've left. So, everything is important.

In MATHEMATICS ,

You should take a problem book for JEE main and start solving. That's the best way to go with Maths.

Chapters like

• Complex numbers and quadratic equations
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• Matrices and determinants
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• Sets, relations and functions
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• Mathematical induction
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• Permutations and combinations
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• Mathematical reasoning
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• Limit, continuity and differentiability
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• Integral calculus
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• Three-dimensional geometry
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• Differential equations
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• Binomial theorem and its simple applications
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• Sequences and series
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• Vector algebra
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• Statistics and probability
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• Trigonometry
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• Co-ordinate geometry
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Questions from all these chapters will come in JEE main both papers.

YOU CAN CLICK ON THE CHAPTERS TO GET MORE DETAIL ON THE PARTICULAR CHAPTER.

Hope it helps and all the best!