Free study guide
Physics Formulas for JAMB & WAEC
Every formula you need for JAMB, WAEC, NECO and WASSCE physics — grouped by topic and built to read on a phone. Bookmark this page and revisit it in the days before the exam.
1. Mechanics & Motion
Linear motion, projectile motion, Newton's laws, work, energy, and power.
| Quantity | Formula |
|---|---|
| Velocity | v = u + at |
| Distance (1D motion) | s = ut + ½at² |
| Velocity² (no time) | v² = u² + 2as |
| Average velocity | v̄ = (u + v) / 2 |
| Newton's 2nd Law | F = ma |
| Momentum | p = mv |
| Impulse | Ft = mv − mu |
| Weight | W = mg |
| Work | W = Fs cosθ |
| Kinetic energy | KE = ½mv² |
| Potential energy | PE = mgh |
| Power | P = W / t = Fv |
| Projectile range | R = (u² sin 2θ) / g |
| Projectile max height | H = (u² sin²θ) / 2g |
| Time of flight | T = (2u sinθ) / g |
| Circular motion (centripetal) | F = mv² / r |
| Angular velocity | ω = 2π / T = 2πf |
2. Gravitation & Simple Harmonic Motion
| Quantity | Formula |
|---|---|
| Newton's law of gravitation | F = GMm / r² |
| Acceleration due to gravity | g = GM / r² |
| Escape velocity | vₑ = √(2gR) |
| Period of a pendulum | T = 2π√(l / g) |
| Period of mass on spring | T = 2π√(m / k) |
| SHM displacement | y = A sin(ωt) |
| SHM max velocity | vₘₐₓ = Aω |
3. Pressure, Density & Fluids
| Quantity | Formula |
|---|---|
| Density | ρ = m / V |
| Pressure | P = F / A |
| Pressure in a fluid | P = ρgh |
| Upthrust (Archimedes) | U = ρVg |
| Relative density | RD = density of substance / density of water |
| Hooke's law | F = ke |
| Young's modulus | E = (F × L) / (A × e) |
4. Heat & Thermodynamics
| Quantity | Formula |
|---|---|
| Quantity of heat | Q = mcΔθ |
| Latent heat | Q = mL |
| Linear expansion | ΔL = αL₀Δθ |
| Area expansion | ΔA = 2αA₀Δθ |
| Volume expansion | ΔV = 3αV₀Δθ |
| Boyle's law | P₁V₁ = P₂V₂ |
| Charles' law | V₁ / T₁ = V₂ / T₂ |
| General gas equation | P₁V₁ / T₁ = P₂V₂ / T₂ |
| Ideal gas law | PV = nRT |
| 1st law of thermodynamics | ΔU = Q − W |
5. Waves & Sound
| Quantity | Formula |
|---|---|
| Wave speed | v = fλ |
| Period & frequency | T = 1 / f |
| Speed of sound (string) | v = √(T / μ) |
| Frequency of stretched string | f = (1 / 2L)√(T / μ) |
| Doppler effect (approaching) | f' = f (v / (v − vₛ)) |
| Doppler effect (receding) | f' = f (v / (v + vₛ)) |
| Intensity of sound | I = P / A |
6. Light & Optics
| Quantity | Formula |
|---|---|
| Snell's law | n = sin i / sin r |
| Refractive index (depth) | n = real depth / apparent depth |
| Critical angle | sin C = 1 / n |
| Mirror / lens formula | 1/f = 1/u + 1/v |
| Magnification | m = v / u = image size / object size |
| Power of a lens | P = 1 / f (in metres) |
| Lens combination | 1/F = 1/f₁ + 1/f₂ |
7. Electricity & Magnetism
| Quantity | Formula |
|---|---|
| Ohm's law | V = IR |
| Electric power | P = IV = I²R = V² / R |
| Electrical energy | E = Pt = IVt |
| Resistors in series | R = R₁ + R₂ + R₃ |
| Resistors in parallel | 1/R = 1/R₁ + 1/R₂ + 1/R₃ |
| EMF & internal resistance | ε = I(R + r) |
| Capacitance | C = Q / V |
| Capacitors in parallel | C = C₁ + C₂ |
| Capacitors in series | 1/C = 1/C₁ + 1/C₂ |
| Energy in capacitor | E = ½CV² |
| Force on a conductor | F = BIL sinθ |
| Force on a moving charge | F = Bqv sinθ |
| Transformer equation | Vₚ / Vₛ = Nₚ / Nₛ |
| Transformer (ideal) | VₚIₚ = VₛIₛ |
| Coulomb's law | F = kq₁q₂ / r² |
| Electric field strength | E = F / q = V / d |
8. Modern & Atomic Physics
| Quantity | Formula |
|---|---|
| Energy of a photon | E = hf = hc / λ |
| Photoelectric equation | hf = Φ + ½mv² |
| Mass–energy equivalence | E = mc² |
| Radioactive decay | N = N₀e^(−λt) |
| Half-life | t½ = ln 2 / λ = 0.693 / λ |
| de Broglie wavelength | λ = h / mv |
| Bohr's energy levels (H) | Eₙ = −13.6 / n² eV |
9. Key Constants You Must Know
| Quantity | Formula |
|---|---|
| Acceleration due to gravity | g = 9.8 m/s² (use 10 m/s² unless told otherwise) |
| Speed of light | c = 3 × 10⁸ m/s |
| Speed of sound in air | v ≈ 340 m/s |
| Planck's constant | h = 6.63 × 10⁻³⁴ Js |
| Electron charge | e = 1.6 × 10⁻¹⁹ C |
| Electron mass | mₑ = 9.11 × 10⁻³¹ kg |
| Gravitational constant | G = 6.67 × 10⁻¹¹ Nm²/kg² |
| Avogadro's number | Nₐ = 6.02 × 10²³ /mol |
| Universal gas constant | R = 8.314 J/(mol·K) |