Class 12 Physics CBSE 2026: High-Scoring Derivations for February 20 Board Exam

CBSE Class 12 Physics is considered one of the most scoring yet concept-based subjects in the board examination. The CBSE Class 12 Physics Board Exam 2026 will be conducted from 10:30 AM to 01:30 PM on Friday, February 20, 2026.

One of the most important scoring areas in the Physics paper is derivations. These questions typically carry 3 to 5 marks and directly test conceptual clarity, logical flow, and presentation skills. Students who understand the reasoning behind formulas — instead of memorising them mechanically — tend to score significantly higher.

Below is a carefully selected list of the most important Physics derivations for CBSE Class 12 Board Exam 2026 that you must revise thoroughly.

CBSE Class 12 Physics 2026: Most Important Derivations

These derivations are frequently asked in CBSE board exams and are considered high-scoring topics.

Make sure you practise writing them neatly with proper diagrams, stepwise explanation, and clearly boxed final formulas.

Electrostatics

• Application of Gauss’s Law

• Electric Field due to Dipole (Axial Point)

• Electric Field due to Dipole (Equatorial Point)

• Torque on a Dipole in an External Electric Field

• Electric Potential due to Dipole

• Potential Energy of a Dipole in External Field

• Capacitance of a Parallel Plate Capacitor

• Capacitance with Dielectric Slab

Current Electricity

• Drift Velocity of Electrons

• Relation between Electric Current and Drift Velocity

• Wheatstone Bridge

Magnetism & Moving Charges

• Magnetic Field due to Circular Current Loop (at Axis)

• Magnetic Force between Two Parallel Current-Carrying Wires

Ray Optics

• Mirror Formula

• Refraction at Spherical Surface

• Lens Maker’s Formula

• Refraction through a Prism

Atoms & Nuclei

• Radius of nth Orbit (Bohr Model)

• Energy of Electron in nth Orbit

Why Derivations Are Important for CBSE Physics 2026

• Many 3–5 mark questions are directly based on standard derivations.

• Steps carry marks — even if the final answer is partially incorrect.

• Proper diagrams and formula presentation improve scoring chances.

• CBSE often repeats derivations in different formats or values.

CBSE Class 12 Physics 2026: Smart Revision Tips

Scoring high in Physics requires clarity, consistency, and presentation.

Follow these important tips:

• Practise writing each important derivation at least twice before the exam.

• Focus on logical steps instead of rote memorisation.

• Draw neat, well-labelled diagrams wherever required.

• Underline or box the final formula clearly.

• Solve previous year board questions to understand the marking scheme.

• Keep the last 15 minutes in the exam for revision of calculations, signs, and substitutions.

The key to scoring full marks in CBSE Class 12 Physics Board Exam 2026 lies in
Conceptual understanding
Structured presentation
Smart practice.
Mastering these important derivations can significantly boost your overall score.

Revise systematically, stay calm, and trust your preparation.

All the best for your Physics Board Exam 2026!