You must read the topics with more weightage that is the topic from which the maximum number of questions were asked in some previous years. In physics these chapters are as follows-

1. Electrodynamics

2. Mechanics

3. Modern physics

4. Heat and thermodynamics

5. SHM, waves and Optics

Hello,

According to the syllabus the following are the chapters in Physics that has a high  weightage :

Heat and Thermodynamics, Ray Optics, Electromagnetic Waves, Semiconductors, Error and Instrument Analysis, Gravitation, Wave Optics, Photoelectric Effect, Oscillations,Electromagnetic Induction and Alternating Current, Rotation, Kinematics, Electrostatics, Current Electricity and Capacitors, Properties of Matter, Magnetic Effects of Current and Magnetism, Bohr's Atomic Model, Waves and Sound.

Along with the thorough understanding of NCERT texts you should also have a little extra reading which will help in increasing your score.