hello aspirant......

for physics important topics are

newtons laws of motion

elasticity

euatition if continuity

bernoullis theorem

kinematics

fluid mechanics

important topics in chemistry are

s,p,d and f block elements

fajans rule

molecular orbital theory

dipole moment

atomic stucture

inorganic chemistry

important topics in mathematics are

vectors

integrals

derivatives

matrices

trignometric ratios

i hope this information is helpful

all the best.

Hii aspirants

let me clear your doubt.

here I am providing you chapterwise marking scheme for jee main for physics, chemistry and maths for year 2020.these are

For maths.                    Topics% of questions asked

Binomial theorem and its simple applications 2

Differential equations 3

Mathematical Induction 3

Mathematical reasoning 3

Permutations and combinations 4

Trigonometry 4

Sequence and series 5

Sets, Relations and Functions 5

Vector Algebra 5

Three Dimensional Geometry 6

Complex numbers and quadratic equations 7

Matrices and Determinants 7

Statistics and Probability 8

Integral Calculus 9

Limit , continuity and differentiability 10

Co-ordinate geometry15

For chemistry

Some basic concepts in chemistry 5

States of matter 3

Atomic Structure 3

Solutions 5

Chemical Thermodynamics 4

Equilibrium 6

Redox Reaction and Electrochemistry 4

Chemical kinetics 3

Surface Chemistry 1

General Principle and process of Isolation of metals 2

Classification of Elements and Periodic table 3

Hydrogen 3

p- Block Elements5

S - Block Elements (Alkali and Alkaline Earth Metals) 1

Chemical Bonding and Molecular Structure 5

d - and f - BLOCK ELEMENTS 4

Co-ordination Compounds 4

Environmental Chemistry 3

Purification and Characterisation of Organic Compounds 3

Some Basic Principles of Organic Chemistry 3

Hydrocarbons 3

Organic Compounds containing Halogens 2

Organic Compounds containing Oxygen 6

Organic Compounds Containing Nitrogen 1

Polymers 3

Biomolecules 3

Chemistry in Everyday Life 4

Principles Related to Practical Chemistry 3

for physics

Gravitation 2

Work Energy and Power 3

Rotational Motion 3

Kinetic theory of Gases 3

Electromagnetic Induction and Alternating currents 3

Experimental skills 3

Kinematics 3

Laws of motion 3

Oscillations and Waves 3

Atoms And Nuclei 3

Physics and Measurement 4

Properties of Solids and Liquids 5

Magnetic Effects of Current and Magnetism 5

Electromagnetic Waves 5

Communication Systems 5

Dual Nature of Matter and Radiation 6

Current Electricity 8

Thermodynamics9

Electrostatics9

Optics 10

Electronic devices 14

I hope my answet will be helpful for you

Good luck