CBSE Class 12 Physics Compartment 2026: High-Weightage Units to Score 33+ Marks

CBSE Class 12 Physics Compartment Exam 2026 is scheduled for July 15, 2026, and students need a minimum of 23 marks out of 70 in the theory paper (33% threshold) to clear the theory component — targeting 33 to 40 marks gives a safe pass margin that removes any borderline risk.

The Physics theory paper carries 70 marks; the remaining 30 marks from the practical examination are carried forward from the main board exam cycle. Compartment students do not need to cover all 14 chapters equally. Identifying which units carry the most marks and concentrating revision there is the most efficient path to crossing the pass threshold before July 15, 2026.

• CBSE Class 12 Physics theory paper: 70 marks; practical marks (30) are carried forward from the main exam — only the theory paper is re-attempted.
• Minimum theory marks to pass: 23 out of 70 (33%); overall subject pass mark: 33 out of 100.
• Top five units — Optics, Electrostatics, Magnetic Effects, EMI and AC, and Atoms and Nuclei — together carry 46 of the 70 theory marks.
• The compartment exam syllabus is identical to the main board exam; no chapter reduction applies.
• Exam date: July 15, 2026 as per CBSE schedule; result expected four to six weeks after the exam.

CBSE Class 12 Physics Compartment Paper Pattern 2026

The compartment exam uses the same paper pattern as the main board exam. The theory paper is for 70 marks and is split into five sections. Internal choices are available in Sections B through E, allowing you to skip a difficult question and attempt the alternative from a chapter you know better.

Section A alone carries 18 marks and can be attempted without writing lengthy solutions. Memorising definitions, SI units, key formulas, and one-line concept statements is enough to score well across all 18 MCQ and assertion-reason questions — treat this section as your quickest guaranteed marks.

Unit-wise Marks Distribution for CBSE Class 12 Physics 2026

The table below shows the approximate mark allocation per unit in the 70-mark theory paper based on the CBSE 2025-26 sample paper and marking scheme. Actual distribution in the compartment paper may vary slightly.

High-Weightage Units to Prioritise for the Compartment Exam

Units I, III, IV, VI, and VIII together account for 46 of the 70 theory marks. Covering these five units thoroughly — even at a formula-and-numericals level — puts 33 to 40 marks well within reach without needing to revise every chapter in the syllabus.

Unit VI — Optics (14 Marks): Start Here

Optics is the single largest unit in the Physics paper and the top priority for every compartment student. Chapter 9 (Ray Optics and Optical Instruments) tests mirror and lens formulas, refraction at plane and spherical surfaces, total internal reflection, the prism, and optical instruments such as the microscope and telescope. Chapter 10 (Wave Optics) tests Huygens principle, Young’s double-slit experiment, diffraction, and polarisation.

• Must-practise in Ray Optics: mirror formula with sign convention, lens formula, lens maker’s equation, refraction through prism (minimum deviation), total internal reflection, and the simple microscope and telescope.
• Must-practise in Wave Optics: YDSE fringe width derivation and formula, conditions for bright and dark fringes, single-slit diffraction pattern.
• Solving 10 to 15 NCERT back-exercises from Chapter 9 is sufficient to target 6 to 8 marks from Ray Optics alone.

Unit I — Electrostatics (8 Marks)

Chapters 1 and 2 test Coulomb’s law, electric field due to point charges and dipoles, Gauss’s law applications, electric potential, equipotential surfaces, capacitance, and energy stored in a capacitor. MCQs and very-short-answer questions from Electrostatics are among the most predictable question types in the CBSE paper and can be scored without lengthy derivations — making this a high-efficiency target for compartment preparation.

Unit III — Magnetic Effects of Current and Magnetism (8 Marks)

Chapter 4 covers Biot-Savart law, Ampere’s circuital law, force on a moving charge in a magnetic field, torque on a current loop, and the moving coil galvanometer. Chapter 5 covers magnetic properties of materials and Earth’s magnetism. Force on a charged particle in a magnetic field and galvanometer-to-ammeter or galvanometer-to-voltmeter conversion questions appear consistently in CBSE papers and are direct formula applications.

Unit IV — Electromagnetic Induction and Alternating Currents (8 Marks)

Chapter 6 covers Faraday’s laws of electromagnetic induction, Lenz’s law, self-inductance, mutual inductance, and eddy currents. Chapter 7 covers RMS and peak values in AC, reactance, impedance, power in AC circuits, LC oscillations, and transformers. Transformer efficiency numericals and AC series circuit (LCR) resonance problems are high-frequency CBSE question types that can be prepared quickly from NCERT solved examples.

Unit VIII — Atoms and Nuclei (8 Marks)

Chapter 12 covers Rutherford’s nuclear model, Bohr’s model of the hydrogen atom, and wavelength calculations using the hydrogen spectrum (Rydberg formula). Chapter 13 covers radioactive decay, half-life, binding energy per nucleon, mass defect, and nuclear reactions. Bohr model energy level numericals and radioactive decay half-life calculations are direct formula questions that a student can master in one to two focused study sessions.

Chapter-wise Study Plan to Score 33 Plus Marks

The plan below is designed for students with 10 to 14 days before the compartment exam on July 15, 2026. Chapters are ordered by marks potential and the speed at which a formula-focused revision pays off.

Completing only the first four rows of this plan — Optics, Electrostatics, Current Electricity, and Atoms and Nuclei — can yield 24 to 31 marks in the theory paper. When added to practical marks typically in the range of 18 to 26 out of 30, the combined total crosses 33 comfortably for most students.

Preparation Tips for CBSE Class 12 Physics Compartment Exam 2026

• NCERT is your only textbook. CBSE compartment papers are set directly from NCERT Physics Parts 1 and 2. Solve every in-text example and chapter-end exercise in NCERT before using any other resource.
• Download the CBSE 2025-26 sample paper from cbse.gov.in. The official sample paper shows the exact marking scheme, section structure, and internal choice pattern for the current exam cycle.
• Treat Section A as guaranteed marks. All 18 MCQ and assertion-reason questions in Section A can be attempted without writing solutions. Memorising definitions, units, key formulas, and brief concept statements is enough to score 12 to 15 in this section alone.
• Always read both options before answering in Sections B through E. Internal choices are designed so one question is typically from a more conceptual chapter and the other from a more formula-based one — choose the option that plays to your preparation.
• Write formulas and draw labelled diagrams in every applicable answer. CBSE awards step marks for correct formulas and diagrams even when the final numerical answer is wrong. A clearly written formula earns 1 mark; a labelled diagram earns another — never skip these steps.
• Attempt every question without exception. There is no negative marking in CBSE exams. A blank answer scores zero; a partially answered question can score 1 to 2 marks through CBSE’s step-marking scheme. Writing something is always better than leaving it blank.