Chapters in Volume 1 and 2#
The Physics textbook for HSC second year is in two volumes: Units 1 to 5 in Volume 1 and Units 6 to 11 in Volume 2. These are the books in use for 2026-27; state officials have said revised textbooks for Classes 4 to 12 are planned for 2027-28.
The public exam theory paper is 70 marks, and the March 2026 Physics exam was held on 13 March 2026. The March 2027 HSC Physics public exam is scheduled for 23 March 2027. In the pattern used in recent public papers, Part II asks for any six of nine 2-mark questions with Q.24 compulsory, Part III asks for any six of nine 3-mark questions with Q.33 compulsory, and Part IV has five 5-mark questions, each with an A or B choice. Long answers can come from either volume, so prepare both.
Book-back answers by chapter#
Book-back questions are the exercises at the end of each unit: multiple choice, short answers, long answers and numerical problems. Instead of copying a ready-made 12th physics book back answers set, use the notes below to write your own, then check them against the textbook.
How to write any book-back answer
- 2 marks: a definition or law in one or two sentences, plus the formula and SI unit.
- 3 marks: the statement, a short explanation and either a labelled diagram or the key equation.
- 5 marks: a derivation or a full explanation: diagram, assumptions, step-by-step working, final result in a box, and one line on what the result means.
- Numericals: write the given values with units, the formula, substitution and the answer with its unit.
Unit 1: Electrostatics
Key points: Coulomb's law and the principle of superposition, electric field lines, the electric dipole (field and potential on the axial and equatorial lines, torque in a uniform field), Gauss's law and its applications (infinite wire, infinite plane sheet, spherical shell), capacitors in series and parallel, energy stored in a capacitor, dielectrics and polarisation, action of points and the Van de Graaff generator.
How to answer: always draw the field or charge diagram first. For Gauss's law applications, state the Gaussian surface you choose and why the field is constant over it.
Unit 2: Current Electricity
Key points: drift velocity and current density, microscopic form of Ohm's law, resistivity and its temperature dependence, combination of resistors, Kirchhoff's rules, Wheatstone bridge, meter bridge and potentiometer, Joule's law of heating, and thermoelectric effects (Seebeck, Peltier, Thomson).
How to answer: for bridge circuits, draw a neat circuit diagram, write the balance condition and show how the unknown resistance is found. Name each Kirchhoff loop you use.
Unit 3: Magnetism and Magnetic Effects of Electric Current
Key points: Earth's magnetic field, magnetic dipole and torque, tangent law and tangent galvanometer, Biot–Savart law (circular coil, straight conductor), Ampère's circuital law (solenoid, toroid), Lorentz force, the cyclotron, force between two parallel conductors and the moving coil galvanometer.
How to answer: label the direction of current and field in every diagram, and state the right-hand rule you are using.
Unit 4: Electromagnetic Induction and Alternating Current
Key points: Faraday's laws and Lenz's law, motional emf, eddy currents and their uses, self and mutual induction, the AC generator, the transformer and its losses, RMS values, phasors, LR, RC and series RLC circuits, resonance, power and power factor, LC oscillations.
How to answer: for the AC generator and transformer, give construction, principle and working in separate short paragraphs with a labelled diagram. For RLC, draw the phasor diagram before deriving impedance.
Unit 5: Electromagnetic Waves
Key points: displacement current, Maxwell's equations in integral form, properties of electromagnetic waves, sources of EM waves, the electromagnetic spectrum and its uses, and types of spectra.
How to answer: write each Maxwell equation with its name and a one-line physical meaning. For the spectrum, a table of wave type, wavelength range and one use earns marks quickly.
Unit 6: Ray Optics
Key points: reflection and spherical mirrors, refraction and Snell's law, total internal reflection and its applications (including optical fibres), refraction at a spherical surface, thin lens and lens maker's formula, power of a lens, the prism and angle of minimum deviation, dispersion and scattering.
How to answer: follow the Cartesian sign convention consistently and mark it on the ray diagram.
Unit 7: Wave Optics
Key points: Huygens' principle and the laws of reflection and refraction from it, interference and Young's double slit experiment, interference in thin films, diffraction at a single slit, resolving power, polarisation (Malus' law, Brewster's law, polaroids), and optical instruments (simple and compound microscope, telescopes).
How to answer: for Young's experiment, derive the path difference from the geometry and then the fringe width; for instruments, give the ray diagram and the magnification formula.
Unit 8: Dual Nature of Radiation and Matter
Key points: photoelectric effect and its laws, Einstein's photoelectric equation, photo cells, de Broglie waves and wavelength, the Davisson–Germer experiment and the electron microscope, and X-rays.
How to answer: list the laws of photoelectric emission as numbered points, then explain how Einstein's equation accounts for each one.
Unit 9: Atomic and Nuclear Physics
Key points: discharge through gases and the electron, atom models and the Bohr model (radius and energy of orbits), the hydrogen spectrum, nuclear size and density, mass defect and binding energy, radioactivity and the decay law, half-life and mean life, nuclear fission and fusion, and nuclear reactors.
How to answer: for binding energy problems, show the mass defect in atomic mass units and convert using 1 u = 931.5 MeV (use the value your textbook gives).
Unit 10: Electronics and Communication
Key points: semiconductors and doping, the p-n junction diode and its characteristics, rectifiers, Zener diode, LED, photodiode and solar cell, bipolar junction transistors and the common emitter configuration, the transistor as a switch and amplifier, logic gates, Boolean algebra and De Morgan's theorems, modulation, and elements of communication systems including fibre-optic communication.
How to answer: draw circuit symbols correctly, give truth tables for every gate, and sketch input and output waveforms for rectifiers.
Unit 11: Recent Developments in Physics
Key points: nanoscience and nanotechnology, robotics, physics in medical diagnosis and therapy, particle physics and cosmology (black holes and gravitational waves).
How to answer: short, factual points with one example each are enough. This unit is light, so revise it for quick 1-mark and 2-mark marks.
Formulas#
| Topic | Formula |
|---|---|
| Coulomb's law | F = (1/4πε₀) q₁q₂/r² |
| Field of a point charge | E = (1/4πε₀) q/r² |
| Dipole field, axial line (r ≫ a) | E = (1/4πε₀) 2p/r³ |
| Dipole field, equatorial line (r ≫ a) | E = (1/4πε₀) p/r³ |
| Parallel plate capacitor | C = ε₀A/d (with dielectric: C = εᵣε₀A/d) |
| Energy in a capacitor | U = ½CV² |
| Current and drift velocity | I = nAevd (vd = drift velocity) |
| Resistance | R = ρl/A |
| Temperature dependence | ρT = ρ₀[1 + α(T − T₀)] |
| Wheatstone bridge balance | P/Q = R/S |
| Joule heating | H = I²Rt |
| Long straight wire | B = μ₀I/2πr |
| Centre of circular coil | B = μ₀NI/2R |
| Long solenoid | B = μ₀nI |
| Cyclotron frequency | f = qB/2πm |
| Force between parallel wires (per unit length) | F/l = μ₀I₁I₂/2πd |
| Faraday's law | ε = −dΦ/dt |
| Motional emf | ε = Blv |
| Transformer | Vs/Vp = Ns/Np |
| RMS current | Irms = I₀/√2 |
| Reactances | XL = ωL, XC = 1/ωC |
| Series RLC impedance | Z = √(R² + (XL − XC)²) |
| Resonant frequency | f₀ = 1/(2π√(LC)) |
| AC power | P = Vrms Irms cos φ |
| Speed of EM waves | c = 1/√(μ₀ε₀) = E₀/B₀ |
| Lens formula | 1/f = 1/v − 1/u |
| Lens maker's formula | 1/f = (n − 1)(1/R₁ − 1/R₂) |
| Snell's law | n₁ sin i = n₂ sin r |
| Critical angle | sin ic = 1/n |
| Prism | n = sin[(A + D)/2] / sin(A/2) |
| Fringe width | β = λD/d |
| Malus' law | I = I₀ cos²θ |
| Brewster's law | tan ip = n |
| Einstein's equation | hν = hν₀ + ½mv²max |
| de Broglie wavelength | λ = h/p = h/mv |
| Bohr radius (hydrogen) | rₙ = 0.529 n² Å |
| Bohr energy (hydrogen) | Eₙ = −13.6/n² eV |
| Radioactive decay | N = N₀e^(−λt) |
| Half-life | T½ = 0.6931/λ |
| Transistor gains | β = IC/IB, α = IC/IE, β = α/(1 − α) |
Important questions#
The Physics paper rewards complete, well-labelled long answers. Use this list to plan your revision; it is based on the core derivations and explanations in each unit, not on any published weightage (DGE does not publish one).
5-mark questions to master
- Electric field and potential due to a dipole; applications of Gauss's law; energy stored in a capacitor.
- Kirchhoff's rules applied to the Wheatstone bridge; meter bridge; potentiometer.
- Tangent galvanometer; magnetic field of a circular coil using the Biot–Savart law; cyclotron; moving coil galvanometer.
- AC generator; transformer; series RLC circuit and resonance.
- Maxwell's equations; properties of EM waves.
- Lens maker's formula; prism and angle of minimum deviation; Young's double slit experiment; polarisation by polaroids; compound microscope.
- Laws of photoelectric effect and Einstein's explanation; de Broglie wavelength of electrons.
- Bohr model of hydrogen; binding energy and nuclear stability; nuclear reactor.
- Full-wave rectifier; transistor characteristics in CE mode; De Morgan's theorems; fibre-optic communication.
2-mark and 3-mark questions
- Definitions with SI units: electric flux, capacitance, drift velocity, resistivity, magnetic dipole moment, self-inductance, power factor, critical angle, work function, half-life.
- Short explanations: lightning arrester, eddy currents, Seebeck effect, why the sky is blue, total internal reflection, LED, Zener diode as a voltage regulator.
- One-step numericals from every unit using the formula table above.
If a derivation will not stick, work through it with a teacher in our live Physics classes and then write it out yourself twice from memory.
12 physics guide tamil medium notes#
Tamil-medium students study the same 11 units and write the same paper. Recent public papers print each question in both Tamil and English, so learn the Tamil technical words and their English equivalents together.
Tamil unit names
Confirm the exact wording of each title against the contents page of your Tamil-medium textbook.
⇆ Swipe sideways to see the whole table
| அலகு | தலைப்பு | English |
|---|---|---|
| 1 | நிலை மின்னியல் | Electrostatics |
| 2 | மின்னோட்டவியல் | Current Electricity |
| 3 | காந்தவியல் மற்றும் மின்னோட்டத்தின் காந்த விளைவுகள் | Magnetism and Magnetic Effects of Electric Current |
| 4 | மின்காந்தத் தூண்டலும் மாறுதிசை மின்னோட்டமும் | Electromagnetic Induction and Alternating Current |
| 5 | மின்காந்த அலைகள் | Electromagnetic Waves |
| 6 | கதிர் ஒளியியல் | Ray Optics |
| 7 | அலை ஒளியியல் | Wave Optics |
| 8 | கதிர்வீச்சு மற்றும் பருப்பொருளின் இருமைப் பண்பு | Dual Nature of Radiation and Matter |
| 9 | அணு மற்றும் அணுக்கரு இயற்பியல் | Atomic and Nuclear Physics |
| 10 | எலக்ட்ரானியல் மற்றும் தகவல் தொடர்பு அமைப்புகள் | Electronics and Communication |
| 11 | இயற்பியலின் அண்மைக்கால வளர்ச்சிகள் | Recent Developments in Physics |
Short Tamil glossary
| English | தமிழ் |
|---|---|
| Electric charge | மின்னூட்டம் |
| Electric field | மின்புலம் |
| Electric potential | மின்னழுத்தம் |
| Capacitor | மின்தேக்கி |
| Resistance | மின்தடை |
| Magnetic field | காந்தப்புலம் |
| Alternating current | மாறுதிசை மின்னோட்டம் |
| Wavelength | அலைநீளம் |
| Frequency | அதிர்வெண் |
| Refraction | ஒளிவிலகல் |
| Interference | குறுக்கீட்டு விளைவு |
| Diffraction | விளிம்பு விளைவு |
| Photoelectric effect | ஒளிமின் விளைவு |
| Radioactivity | கதிரியக்கம் |
| Semiconductor | குறைகடத்தி |
Formulas, symbols and SI units are the same in both media. Check the spelling of each term against the glossary in your Tamil-medium textbook, because examiners follow the textbook's wording.
About 12th physics guide PDF files
The official textbooks for both media can be read on the Tamil Nadu textbooks website. Avoid copied guide PDFs: they often contain errors, and writing your own answers from the textbook is what helps you remember them in the exam.
For Maths support alongside Physics, use our 12th maths important questions. Our guide to the 12th public question paper explains the paper pattern and time table, and CBSE-style practice for the same topics is in our list of derivations of physics class 12. For every Tamil Nadu State Board subject, see the Samacheer Kalvi hub.