NEB Class 12 Physics Notes Handwritten PDF

Welcome to the most complete collection of NEB Class 12 Physics handwritten notes in Nepal free to download as PDF. These notes are prepared strictly following the CDC 2082 curriculum issued by the Curriculum Development Centre, Nepal and verified by experienced Physics teachers.

All 25 chapters of NEB Class 12 Physics are covered from Rotational Dynamics to Recent Trends in Physics organized exactly as per the official NEB syllabus sequence. Whether you are starting your year-long preparation or doing last-minute revision before board exams, these notes give you everything in one place: all important derivations, formulas, numerical examples, short questions, and diagrams that are asked in the NEB board exam.

About These NEB Class 12 Physics Notes

These handwritten notes have been prepared and verified by Physics teachers with experience teaching NEB Science students in Nepal. The notes are written in clear, readable handwriting and follow the exact chapter sequence of the CDC 2082 Physics syllabus the same syllabus used for the current NEB Grade 12 board examination.

What makes these notes reliable:

• Written and verified by experienced NEB Physics teachers
• Follows the official CDC 2082 curriculum chapter sequence exactly
• All 25 chapters covered no chapter is missing or incomplete
• Important derivations are written step-by-step as required in board exam
• Key formulas are highlighted in each chapter for quick revision
• Numerical examples follow the exact format expected in NEB board answers
• Updated for NEB 2082 not the older 2076 or 2080 syllabus

Who these notes are for:

• Teachers looking for reference material for NEB Physics teaching
• NEB Grade 12 Science students preparing for the board exam
• Students who want free handwritten notes instead of buying printed guides
• Students looking for quick revision material before the board exam

We aim to make studying easier for students by giving them the right materials to prepare for exams.

NEB Class 12 Physics Notes Handwritten PDF List

Mechanics
1	Rotational dynamics	View Notes /Download Notes
2	Periodic Motion	View Notes /Download Notes
3	Fluid statics	View Notes /Download Notes

Heat and Thermodynamics
1	First law of Thermodynamics	View Notes /Download Notes
2	Second law of Thermodynamics	View Notes /Download Notes

Wave and Optics
1	Wave motion	View Notes /Download Notes
2	Mechanical waves	View Notes /Download Notes
3	Wave in pipes and strings	View Notes /Download Notes
4	Acoustic phenomena	View Notes /Download Notes
5	Nature and propagation of light	View Notes /Download Notes
6	Interference	View Notes /Download Notes
7	Diffraction	View Notes /Download Notes
8	Polarization	View Notes /Download Notes

Electricity and Magnetism
1	Electrical circuits	View Notes /Download Notes
2	Thermoelectric effects	View Notes /Download Notes
3	Magnetic field	View Notes /Download Notes
4	Magnetic properties of materials	View Notes /Download Notes
5	Electromagnetic Induction	View Notes /Download Notes
6	Alternating currents	View Notes /Download Notes

Modern physics
1	Electrons	View Notes /Download Notes
2	Photons	View Notes /Download Notes
3	Semiconductor Devices	View Notes /Download Notes
4	Quantization of Energy	View Notes /Download Notes
5	Radioactivity and Nuclear Reaction	View Notes /Download Notes
6	Recent Trends in Physics	View Notes /Download Notes

---

What’s Covered NEB Class 12 Physics All Units

The NEB Class 12 Physics syllabus (CDC 2082) has 128 prescribed teaching hours divided into 5 units and 25 chapters. Here is a detailed breakdown of what is covered in these notes:

Unit 1: Mechanics (3 Chapters)

Chapter 1 Rotational Dynamics covers equations of angular motion, moment of inertia and its derivations for different bodies (uniform rod, solid cylinder, sphere), radius of gyration, torque and angular acceleration (τ=Iα), work and power in rotational motion, angular momentum, and the principle of conservation of angular momentum with real-life examples.

Chapter 2 Periodic Motion covers the definition and equation of SHM (a=−ω²x), displacement and velocity in SHM, energy in SHM (KE=½mω²(A²−x²), PE=½mω²x²), derivation of time period for spring-mass system (T=2π√(m/k)) and simple pendulum (T=2π√(L/g)), damped oscillation types, forced oscillation, and resonance with examples.

Chapter 3 Fluid Statics covers pressure in fluids, Archimedes’ principle, Pascal’s law and hydraulic press, surface tension and surface energy, excess pressure in soap bubble (4T/r) and liquid drop (2T/r), angle of contact and capillarity (h=2Tcosθ/ρgr), viscosity and Newton’s formula, Poiseuille’s formula (Q=πPr⁴/8ηl), Stokes law and terminal velocity (v_t=2r²(ρ−σ)g/9η), equation of continuity (A₁v₁=A₂v₂), and Bernoulli’s equation with applications.

Unit 2: Heat and Thermodynamics (2 Chapters)

Chapter 4 First Law of Thermodynamics covers thermodynamic systems and processes, internal energy as a state function, statement of first law (dQ=dU+PdV), specific heats Cp and Cv, Mayer’s relation (Cp−Cv=R), isothermal process (PV=constant, W=nRT ln(V₂/V₁)), adiabatic process (PVγ=constant), isobaric and isochoric processes, PV diagrams and work done as area under curve.

Chapter 5 Second Law of Thermodynamics covers Kelvin-Planck and Clausius statements, heat engine efficiency (η=1−Q₂/Q₁), Carnot cycle four stages and Carnot efficiency (η=1−T₂/T₁), Otto cycle and efficiency (η=1−1/r^(γ−1)), Diesel cycle comparison with Otto, refrigerator working principle and COP (=Q₂/W), and entropy as measure of disorder (ΔS≥0).

Unit 3: Waves and Optics (8 Chapters)

Chapter 6 Wave Motion covers progressive wave parameters, wave equation (y=A sin(ωt−kx)), phase and phase difference (Δφ=2πΔx/λ), stationary wave formation and equation (y=2A cos(kx) sin(ωt)), nodes and antinodes, and comparison of progressive vs stationary waves.

Chapter 7 Mechanical Waves covers general formula for wave speed (v=√(elastic property/inertial property)), Newton’s formula (v=√(P/ρ)=280 m/s) and its error, Laplace correction for adiabatic propagation (v=√(γP/ρ)=332 m/s), speed in solids (v=√(Y/ρ)) and liquids (v=√(B/ρ)), effect of temperature (v∝√T, +0.61 m/s per °C), pressure (no effect), and humidity (moist air faster).

Chapter 8 Waves in Pipes and Strings covers stationary waves in closed organ pipe (f₁=v/4L, odd harmonics only), open organ pipe (f₁=v/2L, all harmonics), comparison of open and closed pipes, end correction (e≈0.6r), velocity of transverse wave in string (v=√(T/μ)), harmonics formula (fₙ=n/2L×√(T/μ)), and three laws of string vibration (length, tension, mass).

Chapter 9 Acoustic Phenomena covers characteristics of sound (intensity, loudness in dB, pitch, quality/timbre), Doppler effect concept and general formula (f’=f(v±v₀)/(v∓vₛ)), all four cases with formulas, and applications in radar, Doppler ultrasound, and astronomy (redshift).

Chapter 10 Nature and Propagation of Light covers wave nature of light historical background, Huygens’ principle statement, types of wavefront (spherical, cylindrical, plane), proof of law of reflection using Huygens’ principle, and proof of Snell’s law (sin i/sin r = v₁/v₂) using Huygens’ principle.

Chapter 11 Interference covers conditions for interference (coherent sources), Young’s double slit experiment setup and path difference derivation, constructive (Δ=nλ) and destructive (Δ=(n+½)λ) interference conditions, fringe width formula (β=λD/d), and effect of changing λ, D, and d on fringe pattern.

Chapter 12 Diffraction covers single slit diffraction pattern and minima condition (a sinθ=nλ), width of central maximum (2λD/a), diffraction grating equation (d sinθ=nλ) and wavelength determination, Rayleigh’s criterion for resolving power (θ_min=1.22λ/D), and difference between diffraction and interference.

Chapter 13 Polarization covers polarized vs unpolarized light, proof that light is transverse, methods of polarization (reflection, refraction, scattering, Polaroid), Brewster’s law derivation (tan i_p=n), Malus’s law (I=I₀cos²θ), and applications of Polaroids (sunglasses, LCD, 3D cinema).

Unit 4: Electricity and Magnetism (6 Chapters)

Chapter 14 Electrical Circuits covers Kirchhoff’s current law (KCL) and voltage law (KVL), Wheatstone bridge balance condition (P/Q=R/S), meter bridge formula (R/X=l₁/(100−l₁)), potentiometer principle and applications (EMF comparison: E₁/E₂=l₁/l₂, internal resistance: r=R(l₁−l₂)/l₂), superconductors and Meissner effect, and galvanometer conversion to ammeter and voltmeter.

Chapter 15 Thermoelectric Effects covers Seebeck effect and thermoelectric EMF, variation of EMF with temperature (neutral temperature T_n, inversion temperature T_i), thermocouple working principle and advantages over mercury thermometer, Peltier effect and its applications (TEC coolers, CPU coolers), and thermopile construction and uses (IR thermometers, thermal imaging).

Chapter 16 Magnetic Field covers Biot-Savart law (dB=μ₀/4π × Idl sinθ/r²) with applications (circular coil, solenoid, straight wire), Ampere’s circuital law (∮B·dl=μ₀I) with applications, Lorentz force (F=qvB sinθ) and circular motion in magnetic field (r=mv/qB), Hall effect and Hall voltage (V_H=BI/ntq), force on current-carrying conductor (F=BIL sinθ), torque on coil (τ=NBIA sinθ), moving coil galvanometer working principle, force between parallel conductors and definition of ampere.

Chapter 17 Magnetic Properties covers magnetic susceptibility (χ=M/H) and relative permeability (μ_r=1+χ), classification of diamagnetic (χ negative, e.g. bismuth, copper), paramagnetic (χ small positive, e.g. aluminium), and ferromagnetic (χ very large, e.g. iron, nickel, cobalt) materials with properties and examples, domain theory of ferromagnetism, hysteresis loop and its significance (retentivity B_r, coercivity H_c, saturation), and selection of magnetic materials for transformer cores vs permanent magnets.

Chapter 18 Electromagnetic Induction covers Faraday’s laws (ε=−NdΦ/dt), Lenz’s law and its basis in energy conservation, motional EMF (ε=BLv), AC generator working principle and EMF derivation (ε=NBAω sinωt), eddy currents causes, disadvantages (laminated cores), and useful applications (induction heating, electromagnetic braking, metal detectors), self-inductance (ε=−LdI/dt), mutual inductance (ε₂=−MdI₁/dt), transformer equation (V₂/V₁=N₂/N₁), and five types of transformer energy losses.

Chapter 19 Alternating Currents covers AC values (peak, RMS: V_rms=V₀/√2), AC through resistor (in phase), inductor (current lags 90°, X_L=ωL), and capacitor (current leads 90°, X_C=1/ωC), series LCR circuit impedance (Z=√(R²+(X_L−X_C)²)), phasor diagrams, series resonance condition (f₀=1/2π√LC), quality factor Q, and power factor (cosφ=R/Z).

Unit 5: Modern Physics (6 Chapters)

Chapter 20 Electrons covers Millikan’s oil drop experiment and charge quantization (e=1.6×10⁻¹⁹ C), motion of electron in electric field (parabolic path) and magnetic field (circular path, r=mv/qB), velocity selector (v=E/B), and Thomson’s experiment for e/m determination (e/m=1.76×10¹¹ C/kg).

Chapter 21 Photons and Photoelectric Effect covers quantum nature of light, photon properties (E=hf, p=h/λ), failure of wave theory to explain photoelectric effect, Einstein’s photoelectric equation (hf=W₀+KE_max), work function and threshold frequency, stopping potential (eV₀=KE_max), Planck’s constant measurement from V₀-f graph, and comparison with thermionic emission.

Chapter 22 Semiconductor Devices covers p-type and n-type semiconductors, PN junction formation and depletion region, forward and reverse bias characteristics, Zener diode and voltage regulation, half-wave and full-wave rectification (with circuit diagrams and efficiency), and logic gates (NOT, AND, OR, NAND, NOR) with truth tables and universal gate property of NAND and NOR.

Chapter 23 Quantization of Energy covers Bohr’s four postulates, derivation of radius of nth orbit (r_n=n²a₀), velocity in nth orbit (v_n=v₁/n), energy of nth orbit (E_n=−13.6/n² eV), spectral series of hydrogen (Lyman, Balmer, Paschen, Brackett, Pfund) and wavelength formula (1/λ=R_H(1/n₁²−1/n₂²)), de Broglie hypothesis (λ=h/mv), X-ray production (Bremsstrahlung and characteristic), properties and applications of X-rays, and Bragg’s law (2d sinθ=nλ).

Chapter 24 Radioactivity covers radioactive decay law (N=N₀e^(−λt)), activity (A=λN), half-life (T₁/₂=0.693/λ), mean life (τ=1/λ=1.44T₁/₂), properties of alpha, beta, and gamma radiation (charge, mass, penetrating power, ionizing power), Geiger-Muller tube construction and working, carbon dating principle (C-14, T₁/₂=5730 years), and difference between natural and artificial radioactivity.

Chapter 25 Recent Trends in Physics covers seismology and types of seismic waves (P-waves, S-waves, Rayleigh waves, Love waves with differences), the 2015 Gorkha Earthquake (magnitude 7.8, epicenter Barpak Gorkha, cause: Indian Plate sliding under Eurasian Plate, over 8800 deaths), gravitational waves (Einstein’s prediction 1916, LIGO detection September 14 2015 from black hole merger 1.3 billion light years away), nanotechnology (1-100 nm scale, quantum effects, applications in medicine, electronics, water purification), and Higgs boson (Higgs field gives mass to particles, discovered at CERN LHC July 4 2012, 2013 Nobel Prize).

NEB Class 12 Physics Board Exam Pattern 2082

Knowing the exam pattern is as important as knowing the content. Here is the complete NEB Class 12 Physics board exam structure for 2082:

Full Marks: 75 (Theory) + 25 (Practical) = 100 total Pass Marks: 27 out of 75 in theory + 8 out of 25 in practical (must pass both separately) Exam Duration: 3 hours for theory paper

Theory Question Paper Structure:

• Group A Multiple Choice: 11 questions × 1 mark = 11 marks (attempt all)
• Group B Short Answer: 10 questions, attempt any 8 × 3 marks = 24 marks
• Group C Long Answer/Derivation: 5 questions, attempt any 4 × 4 marks = 16 marks
• Group D Numerical Problems: 5 questions, attempt any 4 × 4 marks = 16 marks
• Extended Question: 1 question × 8 marks = 8 marks

Most Important Chapters for NEB Board Exam (Based on Past Paper Analysis):

The following chapters have appeared in every NEB Physics board exam for the past 5 years and carry the highest combined marks:

• Electromagnetic Induction (Chapter 18) AC generator derivation, Faraday’s law, transformer losses appear every year
• Alternating Currents (Chapter 19) LCR resonance, impedance numericals appear every year
• Rotational Dynamics (Chapter 1) MI derivation and angular momentum conservation appear every year
• Interference of Light (Chapter 11) Young’s double slit fringe width numericals appear every year
• Photoelectric Effect (Chapter 21) Einstein’s equation numericals appear every year
• Radioactivity (Chapter 24) Decay law and half-life numericals appear every year
• Bohr’s Model (Chapter 23) Energy level and spectral series calculations appear every year
• Fluid Statics (Chapter 3) Stokes law and terminal velocity numericals appear every year

Chapters with guaranteed short questions every year: Laplace correction (Chapter 7), Brewster’s law derivation (Chapter 13), Lenz’s law (Chapter 18), Carnot efficiency (Chapter 5), Doppler effect cases (Chapter 9), and logic gate truth tables (Chapter 22).

How to Study NEB Class 12 Physics for Board Exam

Based on the NEB exam pattern and the weightage of each chapter, here is the most effective study approach for NEB Class 12 Physics:

Step 1 Start with high-weightage chapters Begin your preparation with Electromagnetic Induction (Chapter 18), AC Circuits (Chapter 19), and Rotational Dynamics (Chapter 1). These three chapters alone can contribute 20+ marks to your board paper. Read the handwritten notes carefully, understand each derivation, and practice all related numericals.

Step 2 Master all important derivations In NEB Physics, derivations carry 4 marks each and appear in Group C. The most frequently asked derivations are: moment of inertia of uniform rod, Laplace correction for speed of sound, Carnot efficiency, Young’s double slit fringe width, Brewster’s law (tan ip=n), Faraday’s law and Lenz’s law, AC generator EMF equation, transformer turns ratio, Einstein’s photoelectric equation, Bohr’s model energy levels, and radioactive decay law. Learn all of these step by step.

Step 3 Practice numerical problems daily NEB Physics Group D has 5 numerical problems you must attempt 4. Practice at least 3-5 numericals per chapter from these topics: terminal velocity (Stokes law), fringe width (β=λD/d), LCR resonance frequency, stopping potential (photoelectric effect), radioactive decay (N=N₀e^(−λt)), half-life calculations, Doppler effect frequency shift, and Carnot efficiency.

Step 4 Revise short questions from each chapter Group B short questions (3 marks each) cover definitions, comparisons, and small derivations. Focus on: difference between progressive and stationary waves, comparison of open and closed organ pipes, difference between diamagnetic/paramagnetic/ferromagnetic materials, Seebeck vs Peltier effect, forward vs reverse bias, and types of seismic waves.

Step 5 Solve past NEB question papers After finishing all 25 chapters, solve at least the last 5 years of NEB Class 12 Physics question papers. This shows you the exact question pattern, recurring topics, and the way marks are distributed. You will notice that certain questions repeat almost every year identify these and make sure you can answer them perfectly.

Key Formulas in NEB Class 12 Physics Quick Reference

This formula list is provided as a quick reference for NEB students. Full derivations are available in the chapter-wise handwritten notes above.

Mechanics:

• Moment of inertia of uniform rod (centre): I = ML²/12
• Moment of inertia of uniform rod (end): I = ML²/3
• Torque: τ = Iα (rotational form of Newton’s 2nd law)
• Angular momentum: L = Iω (conserved when τ_external = 0)
• SHM time period (pendulum): T = 2π√(L/g)
• SHM time period (spring): T = 2π√(m/k)
• Terminal velocity: v_t = 2r²(ρ−σ)g / 9η
• Bernoulli’s equation: P + ½ρv² + ρgh = constant

Thermodynamics:

• First law: dQ = dU + PdV
• Mayer’s relation: Cp − Cv = R
• Carnot efficiency: η = 1 − T₂/T₁
• Refrigerator COP: COP = Q₂/W = T₂/(T₁−T₂)

Waves and Optics:

• Speed of sound (Laplace): v = √(γP/ρ)
• Temperature effect: v increases by 0.61 m/s per °C
• Young’s fringe width: β = λD/d
• Diffraction grating: d sinθ = nλ
• Brewster’s law: tan i_p = n
• Malus’s law: I = I₀ cos²θ
• Doppler formula: f’ = f(v ± v₀)/(v ∓ vₛ)

Electricity and Magnetism:

• Biot-Savart (circular coil): B = μ₀NI/2r
• Biot-Savart (solenoid): B = μ₀nI
• Hall voltage: V_H = BI/ntq
• Transformer: V₂/V₁ = N₂/N₁ = I₁/I₂
• AC generator peak EMF: ε₀ = NBAω
• LCR resonance frequency: f₀ = 1/(2π√LC)
• Power factor: cosφ = R/Z

Modern Physics:

• Electron charge: e = 1.6 × 10⁻¹⁹ C
• Electron mass: m = 9.1 × 10⁻³¹ kg
• Specific charge: e/m = 1.76 × 10¹¹ C/kg
• Einstein’s photoelectric equation: hf = W₀ + KE_max
• Bohr’s energy levels: E_n = −13.6/n² eV
• de Broglie wavelength: λ = h/mv
• Radioactive decay law: N = N₀ e^(−λt)
• Half-life: T₁/₂ = 0.693/λ
• Carbon dating half-life (C-14): 5730 years

Class 12 Science Faculty All Subject Notes

• Physics Handwritten Notes PDF
• Chemistry Handwritten Notes PDF
• Biology Handwritten Notes PDF
• Nepali Handwritten Notes PDF
• English Handwritten Notes PDF

Frequently Asked Questions NEB Class 12 Physics Notes

NOTE : “If you want to download the notes Offline Contact us on Social media “