Practice · A–Z glossary
Every term in the subject, in one alphabet.
240 definitions, gathered from the six Part glossaries. Each one says what the term means in a sentence, then hands you the chapter section that builds it properly.
Free to read, all of it. A ● beside a chapter means that section is behind the wall — the link lands on the sample instead.
A
15 termsaccelerationI · Mechanics
rate of change of velocity (slope of v–t; area under a–t gives Δv). The constant-a equations below hold only when a is constant.03 · Rest & Motion — Kinematics
◇ Mechanics glossary● Vectors & Motion in a PlaneAccommodationIV · Optics
the lens reshaping to focus both.6 · Optical instruments & the eye
◇ Optics glossary● Ray Opticsachromatic doubletIV · Optics
An achromatic doublet (converging crown + diverging flint, cemented) cancels it: ω₁/f₁ + ω₂/f₂ = 0.4 · Lenses & power
◇ Optics glossary▸ Ray OpticsAdiabaticIII · Thermodynamics
no heat exchange (ΔQ = 0): PVᵞ = const, TVᵞ⁻¹ = const; the gas cools on expansion.4 · Laws of thermodynamics
◇ Thermodynamics glossary● Kinetic Theory of GasesAmplitude AII · Waves
greatest displacement.1 · Oscillations & SHM
◇ Waves glossary▸ Simple Harmonic MotionAmpère's lawV · Electromagnetism
∮B·dl = μ₀Ienc: the circulation of B counts the threading current. Gives the solenoid (uniform inside, ~0 outside) and toroid instantly.7 · Magnetic field due to a current
◇ Electromagnetism glossary● Moving Charges and MagnetismAngle of deviation (δ)IV · Optics
the turn between incident and emergent rays. As i increases, δ falls to a minimum δm then rises; at δm the passage is symmetric (i₁ = i₂, r₁ = r₂ = A/2) and the ray inside runs parallel to the base.3 · Prism & dispersion
◇ Optics glossary● Ray OpticsAngle of friction λI · Mechanics
resultant of N and f leans at tan λ = μ.06 · Friction
◇ Mechanics glossary● Newton's Laws of MotionAngle of repose θᵣI · Mechanics
steepest slope a block rests on: tan θᵣ = μₛ; independent of mass.06 · Friction
◇ Mechanics glossary● Newton's Laws of MotionAngular frequencyII · Waves
ω = 2πf.0 · Basics, phase & sign convention
◇ Waves glossary▸ Simple Harmonic MotionAngular momentumI · Mechanics
Angular momentum L = Iω conserved with no external torque (the skater's spin).10 · Rotational Mechanics
◇ Mechanics glossary● Rotational MechanicsAnomalous expansion of waterIII · Thermodynamics
water is densest at 4 °C; between 0 and 4 °C it contracts on heating — why ponds freeze top-down and aquatic life survives.1 · Thermometry & thermal expansion
◇ Thermodynamics glossary● Thermal Properties of MatterantinodesII · Waves
Fixed nodes (always still) and antinodes (largest swing); no net energy transport.3 · Superposition & Standing Waves
◇ Waves glossary▸ Waves and SoundApparent depthIV · Optics
an object in a denser medium looks nearer the surface.2 · Refraction & total internal reflection
◇ Optics glossary▸ Ray OpticsArchimedes' principleI · Mechanics
upthrust = weight of fluid displaced; float when average density < fluid density.13 · Fluid Mechanics
◇ Mechanics glossary▸ Fluid MechanicsB
10 termsBanking of a roadI · Mechanics
tilting the road lets the normal force's horizontal component turn the car with no friction at the design speed.07 · Circular Motion
◇ Mechanics glossary● Circular MotionBar magnet = dipoleV · Electromagnetism
of moment M; cut it and each piece is a full magnet with M/2 — poles never come alone. Its field mirrors the electric dipole (axial twice equatorial).8 · Permanent magnets
◇ Electromagnetism glossary▸ Magnetism and MatterBeat frequencyII · Waves
equals the difference of the two frequencies (one loud–soft cycle per hertz of difference). Careful: the envelope repeats twice per carrier-beat, so the audible beat rate is Δf, not Δf/2. Wax on a fork adds mass and lowers its frequency — the trick to tell which of two forks is the faster one.5 · Beats
◇ Waves glossary● Waves and SoundBeatsII · Waves
two tones of nearly equal frequency alternately reinforce and cancel, giving a slow throb in loudness. The result is a fast carrier at the average pitch inside a slow amplitude.5 · Beats
◇ Waves glossary● Waves and SoundBernoulli's equationI · Mechanics
along a streamline, pressure + kinetic + height energy per volume is constant: fast flow, low pressure.13 · Fluid Mechanics
◇ Mechanics glossary● Fluid MechanicsBinding energyVI · Modern Physics
Binding energy comes from the mass defect (Δm·c²); the B/A curve peaks near iron, so fusion of light nuclei and fission of heavy ones both release energy.05 · The Nucleus & Radioactivity
◇ Modern Physics glossary▸ NucleiBiot–SavartV · Electromagnetism
each current element writes a small dB, ⊥ to both the element and the line to the point; integrate for wires, loops, arcs.7 · Magnetic field due to a current
◇ Electromagnetism glossary● Moving Charges and MagnetismblackbodyIII · Thermodynamics
A blackbody (e = 1) is the perfect emitter/absorber; Kirchhoff: good absorbers are good emitters (e = a).6 · Heat transfer
◇ Thermodynamics glossary● Thermal Properties of MatterBragg reflectionVI · Modern Physics
Bragg reflection lets a crystal diffract X-rays; only λ ≤ 2d can satisfy it.03 · X-rays
◇ Modern Physics glossary● AtomsBrewster angleIV · Optics
incidence at which the reflected ray is fully plane-polarised.5 · Wave optics
◇ Optics glossary● Wave OpticsC
22 termsCapacitance C = Q/VV · Electromagnetism
charge stored per volt; set by geometry alone.3 · Capacitors
◇ Electromagnetism glossary● ElectrostaticsCarnot cycleIII · Thermodynamics
two isotherms + two adiabats; the most efficient cycle between two temperatures, η = 1 − Tc/Th. No real engine can beat it (Carnot's theorem).5 · Heat engines & the second law
◇ Thermodynamics glossary● The Laws of ThermodynamicsCentre of curvature (C) / radius (R)IV · Optics
centre and radius of the sphere the mirror is cut from.1 · Reflection
◇ Optics glossary▸ Ray OpticsCentre of massI · Mechanics
mass-weighted mean position; external forces move the COM as if all mass sat there.09 · Centre of Mass, Momentum & Collision
◇ Mechanics glossary● Centre of Mass, Momentum & CollisionsCentripetal accelerationI · Mechanics
velocity turns without changing magnitude; a points at the centre. Something real (tension, gravity, friction, normal) must supply mv² over r — centripetal force is a role, not a new force.07 · Circular Motion
◇ Mechanics glossary▸ Circular MotionCharacteristic linesVI · Modern Physics
Characteristic lines Kα, Kβ — inner-shell transitions fixed by the target element.03 · X-rays
◇ Modern Physics glossary● AtomsChromatic aberrationIV · Optics
f is shorter for violet than red, so white light focuses over a stretch of axis. Longitudinal CA = fr − fv = ω f.4 · Lenses & power
◇ Optics glossaryCircular motion in a magnetic fieldV · Electromagnetism
a charge ⊥ B runs in a circle; the period is independent of speed (the cyclotron's trick). v at an angle adds a drift → helix. Crossed E and B pass only v = E/B (.6 · Magnetic field & force
◇ Electromagnetism glossary▸ Moving Charges and Magnetismclosed pipeII · Waves
An open pipe gives all harmonics; a closed pipe only odd ones.3 · Superposition & Standing Waves
◇ Waves glossary● Waves and SoundCoefficient of restitutionI · Mechanics
Coefficient of restitution e — separation speed over approach speed: e = 1 elastic (KE kept), e = 0 perfectly inelastic (bodies merge, max KE loss).09 · Centre of Mass, Momentum & Collision
◇ Mechanics glossary● Centre of Mass, Momentum & CollisionscoercivityV · Electromagnetism
Hysteresis — B lags H around a loop; retentivity (B left at H = 0), coercivity (reverse H to kill B); loop area = energy lost per cycle.9 · Magnetic properties of matter
◇ Electromagnetism glossary● Magnetism and MatterCoherent sourcesIV · Optics
constant phase difference (needed for a steady interference pattern).5 · Wave optics
◇ Optics glossary▸ Wave OpticsConduction of heatIII · Thermodynamics
energy passed molecule to molecule through a solid (Fourier's law).6 · Heat transfer
◇ Thermodynamics glossary● Thermal Properties of MatterConservative forceI · Mechanics
work independent of path (gravity, spring); only then does potential energy exist.08 · Work & Energy
◇ Mechanics glossary▸ Work, Energy and PowerContinuity equationI · Mechanics
what flows in must flow out: Av constant.13 · Fluid Mechanics
◇ Mechanics glossary● Fluid MechanicsContinuous spectrumVI · Modern Physics
Bremsstrahlung with a sharp cutoff λ_min set only by the tube voltage (Duane–Hunt).03 · X-rays
◇ Modern Physics glossary● AtomsConvection of heatIII · Thermodynamics
heat carried bodily by a moving fluid (natural, from density differences, or forced).6 · Heat transfer
◇ Thermodynamics glossary● Thermal Properties of MatterCoulomb's lawV · Electromagnetism
the force between two point charges, along the line joining them, inverse-square in the separation.1 · Electric field & potential
◇ Electromagnetism glossary▸ ElectrostaticsCritical angle (θc)IV · Optics
the angle of incidence in the denser medium for which the refracted ray grazes the surface (r = 90°).2 · Refraction & total internal reflection
◇ Optics glossary● Ray Opticscritical pointIII · Thermodynamics
Phase (P–T) diagram — maps solid/liquid/gas regions; the triple point is where all three coexist, the critical point ends the liquid–vapour line.2 · Calorimetry & change of state
◇ Thermodynamics glossary● The Laws of Thermodynamicscross productI · Mechanics
Dot product gives a scalar (work); cross product a vector ⊥ to both (torque, L).02 · Physics & Mathematics
◇ Mechanics glossary● Vectors & Motion in a PlaneCyclic processIII · Thermodynamics
the gas returns to its start, so ΔU = 0 and the net work equals the enclosed loop area (clockwise = work out).4 · Laws of thermodynamics
◇ Thermodynamics glossary● The Laws of ThermodynamicsD
16 termsDamped oscillationII · Waves
amplitude decays as e−bt/2m.1 · Oscillations & SHM
◇ Waves glossary● Simple Harmonic Motionde Broglie wavelengthVI · Modern Physics
every moving particle has a wavelength λ = h/p, so matter diffracts too.01 · Photoelectric Effect & Dual Nature
◇ Modern Physics glossary● Dual Nature of Radiation and MatterDegrees of freedom (f)III · Thermodynamics
independent ways a molecule stores energy (equipartition: ½kT each). Monatomic f = 3, diatomic 5, so Cv = (f/2)R and γ = 1 + 2/f.3 · Kinetic theory of gases
◇ Thermodynamics glossary● Kinetic Theory of GasesdielectricV · Electromagnetism
A dielectric (constant K) multiplies C by K by polarising and weakening the internal field.3 · Capacitors
◇ Electromagnetism glossary● ElectrostaticsDiffractionIV · Optics
bending of light into the geometric shadow of an edge or slit.5 · Wave optics
◇ Optics glossary● Wave OpticsDimensional formulaI · Mechanics
every mechanical quantity written as MᵃLᵇTᶜ. An equation must be.01 · Introduction to Physics
◇ Mechanics glossary● Fluid Mechanicsdimensionally homogeneousI · Mechanics
every added term carries the same dimensions.01 · Introduction to Physics
◇ Mechanics glossary● Fluid Mechanicsdip δV · Electromagnetism
Earth's field — described by declination (compass vs true north), dip δ (tilt below horizontal) and the horizontal component BH.8 · Permanent magnets
◇ Electromagnetism glossary● Magnetism and MatterDispersionIV · Optics
a prism spreads white light because n is larger for shorter wavelengths, so violet deviates most, red least.3 · Prism & dispersion
◇ Optics glossary● Ray OpticsDispersive power (ω)IV · Optics
measures the spread relative to the mean deviation. Cauchy: n = A + B/λ².3 · Prism & dispersion
◇ Optics glossary● Ray OpticsDisplacement currentV · Electromagnetism
a changing electric flux acts like a current, id = ε₀ dΦE/dt; it completes Ampère's law and closes the circuit across a capacitor gap.12 · Electromagnetic waves
◇ Electromagnetism glossary▸ Electromagnetic WavesDisplacement methodIV · Optics
a lab way to get f from the two sharp positions of a lens between a fixed object and screen (needs D > 4f).4 · Lenses & power
◇ Optics glossary● Ray OpticsDisplacement vs pressure waveII · Waves
the pressure wave leads the displacement wave by π/2: where displacement is zero (a node of s) the pressure swing is greatest. Amplitude p₀ = Bk·s₀ = ρvω·s₀.4 · Sound Waves
◇ Waves glossary▸ Simple Harmonic MotionDoppler effectII · Waves
relative motion between source and observer changes the observed frequency. Approach bunches the wavefronts (higher pitch); recession stretches them (lower pitch). Only the component along the line joining them counts.6 · Doppler Effect
◇ Waves glossary● Waves and SoundDot productI · Mechanics
Dot product gives a scalar (work); cross product a vector ⊥ to both (torque, L).02 · Physics & Mathematics
◇ Mechanics glossary● Vectors & Motion in a PlaneDrift velocityV · Electromagnetism
electrons crawl at vd (~mm/s) though the signal moves near light speed.4 · Electric current in conductors
◇ Electromagnetism glossary▸ Current ElectricityE
15 termsEddy currentsV · Electromagnetism
induced swirls in bulk metal: brakes and induction stoves (friend), core losses (foe — laminate!).10 · Electromagnetic induction
◇ Electromagnetism glossary● Electromagnetic InductionEfficiencyIII · Thermodynamics
Efficiency η = W/Qh.5 · Heat engines & the second law
◇ Thermodynamics glossary▸ The Laws of ThermodynamicsEinstein's equationVI · Modern Physics
gives the maximum kinetic energy.01 · Photoelectric Effect & Dual Nature
◇ Modern Physics glossary● Dual Nature of Radiation and MatterElectric dipoleV · Electromagnetism
charges ±q a distance d apart; moment p = qd points − → +. Axial field is twice the equatorial field at the same distance.1 · Electric field & potential
◇ Electromagnetism glossary● ElectrostaticsElectric flux ΦV · Electromagnetism
field lines threading a surface; counts E across area, weighted by the tilt cosθ.2 · Gauss's law
◇ Electromagnetism glossary● ElectrostaticsElectrolysisV · Electromagnetism
Faraday: mass deposited ∝ charge passed, and ∝ chemical equivalent (M/z). F = 96,500 C deposits one gram-equivalent.5 · Thermal & chemical effects
◇ Electromagnetism glossary▸ Current ElectricityElectromagnetic spectrumV · Electromagnetism
(λ falling): radio · micro · IR · visible (400–700 nm) · UV · X · γ — the name records the source.12 · Electromagnetic waves
◇ Electromagnetism glossary● Electromagnetic WavesEM wave travelV · Electromagnetism
along E × B; E, B and v are mutually perpendicular.0 · Conventions & the rules of direction
◇ Electromagnetism glossary▸ Electromagnetic WavesEMF εV · Electromagnetism
work per charge by the source; terminal voltage V = ε − Ir droops under load. Max power transfer at R = r (efficiency then only 50%).4 · Electric current in conductors
◇ Electromagnetism glossary● Current ElectricityEmission and absorption spectraIV · Optics
continuous (hot solids), line (atoms), band (molecules), absorption (dark Fraunhofer lines)3 · Prism & dispersion
◇ Optics glossary● Wave OpticsEnd correctionII · Waves
e ≈ 0.6r extends the effective length.3 · Superposition & Standing Waves
◇ Waves glossary● Simple Harmonic MotionEntropyIII · Thermodynamics
Entropy ΔS = Qrev/T measures the one-way spread of energy.5 · Heat engines & the second law
◇ Thermodynamics glossary● The Laws of ThermodynamicsenvelopeII · Waves
The result is a fast carrier at the average pitch inside a slow amplitude envelope.5 · Beats
◇ Waves glossary● Simple Harmonic MotionequipotentialsV · Electromagnetism
E points down the steepest fall of V and is everywhere ⊥ to equipotentials.1 · Electric field & potential
◇ Electromagnetism glossary● ElectrostaticsErrorsI · Mechanics
absolute error Δa; fractional errors add for products and quotients, and powers multiply them. Significant figures survive multiplication as the least count of the inputs.01 · Introduction to Physics
◇ Mechanics glossary▸ Work, Energy and PowerF
6 termsFaraday's law of inductionV · Electromagnetism
a changing flux Φ = BA cosθ induces an EMF equal to its rate of change.10 · Electromagnetic induction
◇ Electromagnetism glossary▸ Electromagnetic InductionField EV · Electromagnetism
= force per unit positive test charge.1 · Electric field & potential
◇ Electromagnetism glossary● ElectrostaticsField linesV · Electromagnetism
leave + charge, enter −; density ∝ strength; they never cross.0 · Conventions & the rules of direction
◇ Electromagnetism glossary● ElectrostaticsFirst law (Newton)I · Mechanics
no net force, no change of velocity (defines inertial frames).05 · Newton's Laws of Motion
◇ Mechanics glossary▸ Newton's Laws of MotionFirst law of thermodynamicsIII · Thermodynamics
ΔQ = ΔU + ΔW (heat in = rise in internal energy + work done by the gas).0 · Conventions & the first law
◇ Thermodynamics glossary▸ The Laws of ThermodynamicsFrequencyII · Waves
f = 1/T (Hz).0 · Basics, phase & sign convention
◇ Waves glossary▸ Simple Harmonic MotionG
1 termsGauss's lawV · Electromagnetism
the total flux through ANY closed surface equals the enclosed charge over ε₀; charge outside contributes nothing. Choose surfaces that match the symmetry (sphere, cylinder, pillbox).2 · Gauss's law
◇ Electromagnetism glossary● ElectrostaticsH
5 termsHeat capacityIII · Thermodynamics
Heat capacity = mc.2 · Calorimetry & change of state
◇ Thermodynamics glossary● Thermal Properties of MatterHeat engineIII · Thermodynamics
takes Qh from a hot source, dumps Qc to a cold sink, and delivers work W = Qh − Qc each cycle.5 · Heat engines & the second law
◇ Thermodynamics glossary● The Laws of ThermodynamicsHeat ΔQIII · Thermodynamics
+ when supplied TO the system, − when released.0 · Conventions & the first law
◇ Thermodynamics glossary● Thermal Properties of MatterHuygens’ principleIV · Optics
every point on a wavefront is a source of secondary wavelets; their envelope is the next wavefront.5 · Wave optics
◇ Optics glossary▸ Wave OpticsHypermetropia (long sight)IV · Optics
near objects blur; eyeball too short; corrected with a convex lens.6 · Optical instruments & the eye
◇ Optics glossary● Ray OpticsI
7 termsIdeal gasIII · Thermodynamics
U depends on temperature alone, U = (f/2)nRT.0 · Conventions & the first law
◇ Thermodynamics glossary▸ Kinetic Theory of GasesInductanceV · Electromagnetism
a coil's flux per ampere: NΦ = LI. It resists changes in current, stores ½LI² in the field, and sets the LR time constant.10 · Electromagnetic induction
◇ Electromagnetism glossary● Electromagnetic InductionIntensity & loudnessII · Waves
intensity falls as 1/r² from a point source.4 · Sound Waves
◇ Waves glossary● Waves and SoundinterferenceII · Waves
in phase (δ = 2nπ) build up, out of phase (δ = (2n−1)π) cancel.3 · Superposition & Standing Waves
◇ Waves glossary● Waves and SoundIsobaricIII · Thermodynamics
Isobaric (const P): W = PΔV.4 · Laws of thermodynamics
◇ Thermodynamics glossary● The Laws of ThermodynamicsIsochoricIII · Thermodynamics
(const V): W = 0, ΔQ = ΔU.4 · Laws of thermodynamics
◇ Thermodynamics glossary● The Laws of ThermodynamicsIsothermalIII · Thermodynamics
(const T, ideal gas): ΔU = 0, W = nRT ln(V₂/V₁).4 · Laws of thermodynamics
◇ Thermodynamics glossary● The Laws of ThermodynamicsJ
1 termsJoule heatingV · Electromagnetism
collisions turn electrical work into heat; the basis of fuses, heaters, bulbs.5 · Thermal & chemical effects
◇ Electromagnetism glossary● Current ElectricityK
5 termsKepler's lawsI · Mechanics
ellipses with the sun at a focus; equal areas in equal times (L conserved); T² ∝ a³.11 · Gravitation
◇ Mechanics glossary● GravitationKinetic frictionI · Mechanics
fixed at μₖN (μₖ < μₛ), opposing sliding.06 · Friction
◇ Mechanics glossary● Newton's Laws of MotionKinetic pressureIII · Thermodynamics
pressure is the drum of molecular impacts on the walls: P = ⅓ρc̄², and the mean translational energy per molecule is ½m c̄² = (3/2)kT — temperature IS molecular kinetic energy.3 · Kinetic theory of gases
◇ Thermodynamics glossary● Kinetic Theory of GasesKirchhoff's circuit lawsV · Electromagnetism
junction (charge) + loop (energy).4 · Electric current in conductors
◇ Electromagnetism glossary● Current ElectricityKirchhoff's radiation lawIII · Thermodynamics
good absorbers are good emitters (e = a). Stefan–Boltzmann: emitted power ∝ T⁴.6 · Heat transfer
◇ Thermodynamics glossary● Thermal Properties of MatterL
10 termsLaplace's correctionII · Waves
corrected it to adiabatic (v = √γP/ρ). It rises with temperature (v ∝ √T) and, in air, with humidity.4 · Sound Waves
◇ Waves glossary● Waves and SoundLatent heat (L)III · Thermodynamics
heat per unit mass absorbed or released at a phase change (fusion, vaporisation) at constant temperature — the plateaus on a heating curve.2 · Calorimetry & change of state
◇ Thermodynamics glossary● Thermal Properties of Matterlateral shiftIV · Optics
the sideways offset of a ray leaving a parallel slab (it emerges parallel to its original path).2 · Refraction & total internal reflection
◇ Optics glossary▸ Ray OpticsLaws of reflectionIV · Optics
the incident ray, reflected ray and normal lie in one plane; angle of incidence = angle of reflection.1 · Reflection
◇ Optics glossary▸ Ray Opticslength contractionVI · Modern Physics
Time dilation (moving clocks run slow) and length contraction (moving rulers shrink along the motion) are reciprocal.06 · Special Relativity
◇ Modern Physics glossary● Special RelativityLenz's lawV · Electromagnetism
induced effects oppose the change in flux that made them — energy conservation in disguise.0 · Conventions & the rules of direction
◇ Electromagnetism glossary● Electromagnetic InductionLenz's minus signV · Electromagnetism
sets the direction (oppose the change).10 · Electromagnetic induction
◇ Electromagnetism glossary● Electromagnetic InductionLongitudinal waveII · Waves
particles move along travel (sound).2 · Wave Motion
◇ Waves glossary▸ Waves and SoundLorentz forceV · Electromagnetism
F = qE + qv×B. The magnetic part is ⊥ v, so it does no work — it only bends the path.6 · Magnetic field & force
◇ Electromagnetism glossary▸ Moving Charges and MagnetismLoudness (decibel)II · Waves
in decibels is β = 10 log(I/I₀).4 · Sound Waves
◇ Waves glossary● Waves and SoundM
14 termsMagnifying powerIV · Optics
ratio of the angle an image subtends at the eye to the angle the object would subtend unaided (at D = 25 cm). Every instrument is angle inflation.6 · Optical instruments & the eye
◇ Optics glossary● Wave OpticsMaxwell distributionIII · Thermodynamics
the spread of speeds, peaking at vmp and skewed to high speeds.3 · Kinetic theory of gases
◇ Thermodynamics glossary● Kinetic Theory of GasesMayer's relationIII · Thermodynamics
Cp − Cv = R.4 · Laws of thermodynamics
◇ Thermodynamics glossary▸ Thermal Properties of MatterMean free path (λ)III · Thermodynamics
average distance a molecule travels between collisions.3 · Kinetic theory of gases
◇ Thermodynamics glossary● Kinetic Theory of GasesMechanical energyI · Mechanics
Mechanical energy E = KE + PE is conserved when only conservative forces act; friction bleeds it into heat.08 · Work & Energy
◇ Mechanics glossary▸ Work, Energy and PowerMelde's experimentII · Waves
relates loop count to tension (p ∝ 1/√T).3 · Superposition & Standing Waves
◇ Waves glossary● Waves and SoundMolar specific heatIII · Thermodynamics
Specific heat (c) — heat to raise unit mass by one degree; molar specific heat per mole.2 · Calorimetry & change of state
◇ Thermodynamics glossary● Kinetic Theory of GasesMolecular speedsIII · Thermodynamics
rms > average > most-probable, all ∝ √T.3 · Kinetic theory of gases
◇ Thermodynamics glossary● Kinetic Theory of GasesMoment of inertiaI · Mechanics
rotational mass; grows with distance² from the axis.10 · Rotational Mechanics
◇ Mechanics glossary● Rotational MechanicsMomentum conservedI · Mechanics
whenever ΣF_ext = 0 — the working law of every collision.09 · Centre of Mass, Momentum & Collision
◇ Mechanics glossary● Centre of Mass, Momentum & CollisionsMoseley's lawVI · Modern Physics
Moseley's law orders elements by nuclear charge Z.03 · X-rays
◇ Modern Physics glossary● AtomsMotional EMFV · Electromagnetism
a rod sweeping flux at speed v generates BLv; on rails it drives a current, feels a retarding force, and the mechanical power in equals the I²R heat out.10 · Electromagnetic induction
◇ Electromagnetism glossary● Electromagnetic Inductionmoving-coil galvanometerV · Electromagnetism
Currents feel it too — force on a wire, torque on a loop with moment m = NIA; a spring restores the moving-coil galvanometer to make deflection ∝ current.6 · Magnetic field & force
◇ Electromagnetism glossary● Moving Charges and MagnetismMyopia (short sight)IV · Optics
distant objects blur; the eyeball is too long; corrected with a concave lens (f = −far point).6 · Optical instruments & the eye
◇ Optics glossary● Ray OpticsN
4 termsn-typeVI · Modern Physics
(donors, majority electrons)04 · Semiconductors & Devices
◇ Modern Physics glossary▸ Dual Nature of Radiation and MatterNear / far pointIV · Optics
closest (25 cm) and farthest (∞) points of clear vision for a normal eye.6 · Optical instruments & the eye
◇ Optics glossaryNewton's law of coolingIII · Thermodynamics
for a small excess over the surroundings, the rate of cooling is proportional to that excess.6 · Heat transfer
◇ Thermodynamics glossary● Thermal Properties of MatternodesII · Waves
Fixed nodes (always still) and antinodes (largest swing); no net energy transport.3 · Superposition & Standing Waves
◇ Waves glossary▸ Waves and SoundO
3 termsOhm's lawV · Electromagnetism
V ∝ I when ρ is constant; ρ rises with temperature in metals, falls in carbon/semiconductors.4 · Electric current in conductors
◇ Electromagnetism glossary● Current Electricityopen pipeII · Waves
An open pipe gives all harmonics; a closed pipe only odd ones.3 · Superposition & Standing Waves
◇ Waves glossaryOrbit energyI · Mechanics
negative — a bound satellite must be given energy to escape.11 · Gravitation
◇ Mechanics glossary● GravitationP
32 termsp-typeVI · Modern Physics
n-type (donors, majority electrons) and p-type (acceptors, majority holes) obey the mass-action law, staying neutral.04 · Semiconductors & Devices
◇ Modern Physics glossary▸ Semiconductor ElectronicsParallel currentsV · Electromagnetism
attract when parallel, repel when anti-parallel — the old definition of the ampere.7 · Magnetic field due to a current
◇ Electromagnetism glossary● Moving Charges and MagnetismParallel-axis theoremI · Mechanics
I about any axis = I_cm + Md².10 · Rotational Mechanics
◇ Mechanics glossary● Rotational MechanicsParaxial rayIV · Optics
rays: close to and nearly parallel with the axis — the clean-image assumption.0 · Cartesian sign convention & basics
◇ Optics glossary▸ Ray OpticsParticle velocityII · Waves
u = ∂y/∂t is the slope of the displacement–time graph.2 · Wave Motion
◇ Waves glossary▸ Simple Harmonic MotionParticle velocity ∂y/∂tII · Waves
≠ wave velocity v. A crest is where the phase = π/2.0 · Basics, phase & sign convention
◇ Waves glossary▸ Simple Harmonic MotionPascal's lawI · Mechanics
an applied pressure change reaches every point undiminished (the hydraulic press).13 · Fluid Mechanics
◇ Mechanics glossary▸ Fluid MechanicsPath difference (Δ)IV · Optics
the extra distance one wave travels — whole λ give brightness, half-λ give darkness.5 · Wave optics
◇ Optics glossary● Wave OpticsPeriod TII · Waves
time for one full cycle.0 · Basics, phase & sign convention
◇ Waves glossary▸ Simple Harmonic MotionPhase (P–T) diagramIII · Thermodynamics
maps solid/liquid/gas regions.2 · Calorimetry & change of state
◇ Thermodynamics glossary● Thermal Properties of MatterPhase constant φII · Waves
where in the cycle the motion starts. Velocity leads displacement by π/2; acceleration by π.1 · Oscillations & SHM
◇ Waves glossary▸ Simple Harmonic MotionPhase differenceII · Waves
from a path gap Δx: Δφ = (2π/λ)·Δx. From a time gap Δt: Δφ = (2π/T)·Δt.0 · Basics, phase & sign convention
◇ Waves glossary● Simple Harmonic MotionPhase of a waveII · Waves
of y = A sin(ωt + φ): φ is the head-start. +φ leads, −φ lags.0 · Basics, phase & sign convention
◇ Waves glossary▸ Waves and Soundphasor / reference circleII · Waves
The projection of uniform circular motion onto a diameter (the phasor / reference circle).1 · Oscillations & SHM
◇ Waves glossary● Simple Harmonic MotionPhotonVI · Modern Physics
light arrives in quanta of energy E = hν = hc/λ and momentum p = h/λ.01 · Photoelectric Effect & Dual Nature
◇ Modern Physics glossary● Dual Nature of Radiation and MatterPlane mirrorIV · Optics
image is virtual, erect, same size, as far behind as the object is in front, laterally inverted.1 · Reflection
◇ Optics glossary▸ Ray OpticsPolarisationIV · Optics
restricting the light’s vibration to one plane — proof light is a transverse wave.5 · Wave optics
◇ Optics glossary● Wave Opticspole / optical centreIV · Optics
Measure all distances from the pole / optical centre along the axis.0 · Cartesian sign convention & basics
◇ Optics glossary● Ray OpticsPotential VV · Electromagnetism
work per unit charge brought from infinity; a scalar. E points down the steepest fall of V and is everywhere ⊥.1 · Electric field & potential
◇ Electromagnetism glossary● ElectrostaticsPotentiometerV · Electromagnetism
compares EMFs by balancing lengths, drawing no current.4 · Electric current in conductors
◇ Electromagnetism glossary● Current ElectricityPower & intensityII · Waves
a string carries P = ½μω²A²v; intensity ∝ A².2 · Wave Motion
◇ Waves glossary● Waves and SoundPower (P)IV · Optics
P = 1/f in dioptres (f in metres); converging +, diverging −. In contact, powers add.4 · Lenses & power
◇ Optics glossary● Wave Opticspower factorV · Electromagnetism
Only the in-phase current does work: power factor cosφ; a pure reactance draws wattless current.11 · Alternating current
◇ Electromagnetism glossary● Alternating CurrentPressureI · Mechanics
Pressure in a still fluid depends only on depth.13 · Fluid Mechanics
◇ Mechanics glossary▸ Fluid MechanicsPrincipal focus (F)IV · Optics
where paraxial rays parallel to the axis converge (concave) or appear to diverge from (convex).1 · Reflection
◇ Optics glossary▸ Ray OpticsPrinciple of calorimetryIII · Thermodynamics
in an insulated mix, heat lost by the hot bodies = heat gained by the cold, until a common equilibrium temperature.2 · Calorimetry & change of state
◇ Thermodynamics glossary● Thermal Properties of MatterProgressive waveII · Waves
a disturbance that carries energy and momentum, not matter.2 · Wave Motion
◇ Waves glossary▸ Waves and SoundProjectileI · Mechanics
independent horizontal (uniform) and vertical (free-fall) motions.03 · Rest & Motion — Kinematics
◇ Mechanics glossary● Vectors & Motion in a PlanePseudo-forceI · Mechanics
in a frame accelerating at a₀, add −ma₀ to every body; only then does ΣF = ma hold inside that frame.05 · Newton's Laws of Motion
◇ Mechanics glossary● Newton's Laws of Motionp–n junctionVI · Modern Physics
a one-way diode: forward bias conducts past the knee V_b, reverse bias blocks.04 · Semiconductors & Devices
◇ Modern Physics glossary● Semiconductor ElectronicsQ
2 termsQuantised orbitsVI · Modern Physics
angular momentum comes in units of h/2π, so only certain radii and energies are allowed. Energy is negative (bound) and rises toward zero as n grows.02 · Bohr Atom & Atomic Spectra
◇ Modern Physics glossary● AtomsQuincke's tubeII · Waves
shows interference by a sliding path difference.4 · Sound Waves
◇ Waves glossary● Waves and SoundR
18 termsRadiation of heatIII · Thermodynamics
emitted as electromagnetic waves, no medium needed.6 · Heat transfer
◇ Thermodynamics glossary● Thermal Properties of MatterRadiation pressureV · Electromagnetism
absorbed energy U carries momentum U/c; reflection doubles the push.12 · Electromagnetic waves
◇ Electromagnetism glossary● Electromagnetic WavesRadioactivityVI · Modern Physics
α, β, γ emissions; the number left decays exponentially, with activity A = λN and half-life t½ = 0.693/λ.05 · The Nucleus & Radioactivity
◇ Modern Physics glossary● NucleiReactanceV · Electromagnetism
frequency-dependent opposition: XL = ωL (V leads I by 90°), XC = 1/ωC (V lags by 90°) — remember CIVIL.11 · Alternating current
◇ Electromagnetism glossary● Alternating CurrentRectifiersVI · Modern Physics
Rectifiers make DC (full-wave ripple = 2f); transistor gains α, β amplify.04 · Semiconductors & Devices
◇ Modern Physics glossary● Semiconductor ElectronicsReflection of a waveII · Waves
at a fixed end the pulse flips (π phase change); at a free end it does not.2 · Wave Motion
◇ Waves glossary▸ Waves and SoundRefractive indexIV · Optics
n = c/v, a measure of optical density. Frequency is fixed at a boundary; speed and wavelength both fall by n. Relative index n₂₁ = n₂/n₁ = v₁/v₂ = λ₁/λ₂.2 · Refraction & total internal reflection
◇ Optics glossary▸ Wave OpticsRefrigerator / heat pumpIII · Thermodynamics
the engine run in reverse: work pumps heat from cold to hot. Rated by coefficient of performance (COP).5 · Heat engines & the second law
◇ Thermodynamics glossary● The Laws of ThermodynamicsRegelationIII · Thermodynamics
ice melting under pressure and refreezing.2 · Calorimetry & change of state
◇ Thermodynamics glossaryRelative velocityI · Mechanics
v_AB = v_A − v_B.03 · Rest & Motion — Kinematics
◇ Mechanics glossary● Kinematics in One DimensionResolution of a vectorI · Mechanics
Aₓ = A cos θ, A_y = A sin θ.02 · Physics & Mathematics
◇ Mechanics glossary▸ Vectors & Motion in a PlaneResolving powerIV · Optics
ability to see two close objects as separate (Rayleigh criterion).5 · Wave optics
◇ Optics glossary● Wave OpticsResonanceII · Waves
driving at the natural frequency ω₀ gives the largest response.1 · Oscillations & SHM
◇ Waves glossary● Simple Harmonic MotionRetentivityV · Electromagnetism
Hysteresis — B lags H around a loop; retentivity (B left at H = 0), coercivity (reverse H to kill B); loop area = energy lost per cycle.9 · Magnetic properties of matter
◇ Electromagnetism glossary● Magnetism and MatterRight-hand gripV · Electromagnetism
thumb along I, fingers curl along B (wire); fingers curl along I, thumb gives B (loop/solenoid).0 · Conventions & the rules of direction
◇ Electromagnetism glossary● Moving Charges and MagnetismRMS valueV · Electromagnetism
the steady DC that heats identically; meters read rms, insulation survives the peak (√2 higher). Mean over a cycle is zero.11 · Alternating current
◇ Electromagnetism glossary▸ Alternating CurrentRolling motionI · Mechanics
the k = I over MR² ratio decides who wins the race downhill; less spin energy, more speed.10 · Rotational Mechanics
◇ Mechanics glossary● Rotational MechanicsS
20 termsSecond law (Newton)I · Mechanics
ΣF = ma per axis.05 · Newton's Laws of Motion
◇ Mechanics glossary▸ Newton's Laws of MotionSecond law of thermodynamicsIII · Thermodynamics
heat will not flow cold → hot unaided (Clausius) and no engine turns all heat into work (Kelvin–Planck).5 · Heat engines & the second law
◇ Thermodynamics glossary● The Laws of ThermodynamicsSeries resonanceV · Electromagnetism
at ω₀ the reactances cancel, Z = R, current peaks; sharpness Q, bandwidth Δω = R/L. Only the in-phase current does work.11 · Alternating current
◇ Electromagnetism glossary● Alternating CurrentSHMI · Mechanics
restoring acceleration proportional to displacement, a = −ω²x; the shadow of uniform circular motion. Period independent of amplitude. Velocity leads displacement by π/2.12 · Simple Harmonic Motion full module lives in Waves ↗
◇ Mechanics glossary● Circular MotionSilvered lensIV · Optics
a lens with one face mirrored behaves as an equivalent mirror; the lens power counts twice.4 · Lenses & power
◇ Optics glossary▸ Ray OpticsSimple harmonic motionII · Waves
acceleration is proportional to displacement and always directed toward the mean position: a = −ω²x. The projection of uniform circular motion onto a diameter (the.1 · Oscillations & SHM
◇ Waves glossary● Simple Harmonic MotionSonic boomII · Waves
vs = v makes the formula diverge.6 · Doppler Effect
◇ Waves glossary● Waves and SoundSpecific heat (c)III · Thermodynamics
heat to raise unit mass by one degree.2 · Calorimetry & change of state
◇ Thermodynamics glossary● Kinetic Theory of GasesSpectral seriesVI · Modern Physics
a jump from n₂ to n₁ emits a photon set by the Rydberg formula; Lyman (n₁=1, UV), Balmer (n₁=2, visible), Paschen (n₁=3, IR). Hydrogen-like ions scale with Z².02 · Bohr Atom & Atomic Spectra
◇ Modern Physics glossary● AtomsspectrometerIV · Optics
Spectra: continuous (hot solids), line (atoms), band (molecules), absorption (dark Fraunhofer lines); a spectrometer (collimator · prism table · telescope) reads A and δm to get n(λ).3 · Prism & dispersion
◇ Optics glossary● Ray OpticsSpeed of soundII · Waves
Newton assumed isothermal (v = √P/ρ, too low)4 · Sound Waves
◇ Waves glossary● Waves and SoundStanding waveII · Waves
two equal waves travelling opposite ways: y = 2A sin(kx) cos(ωt). Fixed.3 · Superposition & Standing Waves
◇ Waves glossary● Waves and SoundState function (ΔU)III · Thermodynamics
(end-states only); ΔQ and ΔW are path functions. Per cycle ΔU = 0.0 · Conventions & the first law
◇ Thermodynamics glossary▸ The Laws of ThermodynamicsStatic frictionI · Mechanics
self-adjusting, anything from 0 up to μₛN; it equals the applied force until slipping.06 · Friction
◇ Mechanics glossary● Newton's Laws of Motionstopping potentialVI · Modern Physics
Einstein's equation gives the maximum kinetic energy; the stopping potential V₀ measures it.01 · Photoelectric Effect & Dual Nature
◇ Modern Physics glossary● Dual Nature of Radiation and MatterstrainI · Mechanics
fractional deformation; their ratio (the modulus) belongs to the material. Elastic below the elastic limit; permanent set beyond the yield point; fracture past the ultimate strength.14 · Mechanical Properties of Matter
◇ Mechanics glossary▸ Properties of MatterStressI · Mechanics
restoring force per area.14 · Mechanical Properties of Matter
◇ Mechanics glossary▸ Properties of MatterStrings & pipesII · Waves
boundary conditions pick discrete frequencies (harmonics).3 · Superposition & Standing Waves
◇ Waves glossary● Waves and SoundSuperpositionII · Waves
where waves overlap, displacements add. Two coherent waves give.3 · Superposition & Standing Waves
◇ Waves glossary● Waves and SoundSurface tensionI · Mechanics
a surface costs energy T per area, so liquids minimise it; a wetting liquid climbs a capillary.14 · Mechanical Properties of Matter
◇ Mechanics glossary● Fluid MechanicsT
14 termsTemperatureIII · Thermodynamics
the quantity that decides the direction of heat flow; measured on the Celsius, Fahrenheit or absolute (Kelvin) scale. Absolute zero (0 K) is the point of least molecular motion.1 · Thermometry & thermal expansion
◇ Thermodynamics glossary● Kinetic Theory of GasesThermal expansionIII · Thermodynamics
most solids grow on heating: linear (α), area/superficial (β) and volume/cubical (γ) coefficients, related α: β: γ = 1: 2: 3.1 · Thermometry & thermal expansion
◇ Thermodynamics glossary▸ Thermal Properties of MatterThermal resistanceIII · Thermodynamics
Thermal resistance R = x/KA adds like electrical resistance: series R = R₁ + R₂, parallel 1/R = 1/R₁ + 1/R₂.6 · Heat transfer
◇ Thermodynamics glossary● Thermal Properties of MatterThermal stressIII · Thermodynamics
a rod clamped so it cannot expand develops a compressive stress YαΔT, independent of length.1 · Thermometry & thermal expansion
◇ Thermodynamics glossary● Thermal Properties of MatterThermoelectricityV · Electromagnetism
a junction pair at different temperatures drives a thermo-emf (Seebeck), parabolic in θ with a neutral temperature (max) and inversion temperature (sign flip). Peltier and Thomson are its reversible cousins.5 · Thermal & chemical effects
◇ Electromagnetism glossary● Current ElectricityThin lensIV · Optics
two refracting surfaces a negligible distance apart. Beyond 2F: real, inverted, small; between F and 2F: real, inverted, large; inside F: virtual, erect, magnified (the magnifier).4 · Lenses & power
◇ Optics glossary● Ray OpticsThird law (Newton)I · Mechanics
forces come in equal-and-opposite pairs on different bodies.05 · Newton's Laws of Motion
◇ Mechanics glossary● Newton's Laws of MotionTime dilationVI · Modern Physics
Time dilation (moving clocks run slow) and length contraction (moving rulers shrink along the motion) are reciprocal.06 · Special Relativity
◇ Modern Physics glossary▸ Special RelativityTorqueI · Mechanics
turning effect, force × lever arm.10 · Rotational Mechanics
◇ Mechanics glossary▸ Rotational MechanicsTotal internal reflectionIV · Optics
beyond θc, all light is reflected back — the basis of optical fibres and the sparkle of diamond.2 · Refraction & total internal reflection
◇ Optics glossary● Ray OpticstransformerV · Electromagnetism
The transformer trades volts for amps at constant power.11 · Alternating current
◇ Electromagnetism glossary● Alternating CurrentTransistorVI · Modern Physics
Rectifiers make DC (full-wave ripple = 2f); transistor gains α, β amplify.04 · Semiconductors & Devices
◇ Modern Physics glossary● Semiconductor ElectronicsTransverse waveII · Waves
particles move ⊥ to travel (waves on a string, light).2 · Wave Motion
◇ Waves glossary▸ Waves and Soundtriple pointIII · Thermodynamics
Phase (P–T) diagram — maps solid/liquid/gas regions; the triple point is where all three coexist, the critical point ends the liquid–vapour line.2 · Calorimetry & change of state
◇ Thermodynamics glossary▸ Thermal Properties of MatterU
2 termsUnit vectorI · Mechanics
Unit vector â = A divided by its magnitude.02 · Physics & Mathematics
◇ Mechanics glossary● Vectors & Motion in a PlaneUniversal law of gravitationI · Mechanics
every pair of masses attracts along the line joining them. g falls off as 1 over r² outside the Earth and grows linearly from zero at the centre.11 · Gravitation
◇ Mechanics glossary▸ GravitationV
5 termsVectorI · Mechanics
magnitude + direction + triangle law of addition.02 · Physics & Mathematics
◇ Mechanics glossary● Vectors & Motion in a PlaneVelocityI · Mechanics
rate of change of displacement (slope of x–t)03 · Rest & Motion — Kinematics
◇ Mechanics glossary▸ Kinematics in One Dimensionvelocity selectorV · Electromagnetism
Crossed E and B pass only v = E/B (velocity selector).6 · Magnetic field & force
◇ Electromagnetism glossary▸ Current ElectricityVirtual imageIV · Optics
they only appear to.0 · Cartesian sign convention & basics
◇ Optics glossary● Ray OpticsViscosityI · Mechanics
fluid friction; a small falling sphere reaches terminal velocity when Stokes' drag balances net weight.14 · Mechanical Properties of Matter
◇ Mechanics glossary● Fluid MechanicsW
12 termsWater equivalentIII · Thermodynamics
Water equivalent w = mc/cwater: the mass of water needing the same heat.2 · Calorimetry & change of state
◇ Thermodynamics glossary● Thermal Properties of MatterWave speedII · Waves
v = fλ = ω/k.0 · Basics, phase & sign convention
◇ Waves glossary● Waves and Soundwave velocityII · Waves
Particle velocity u = ∂y/∂t is the slope of the displacement–time graph; the wave velocity v is fixed by the medium.2 · Wave Motion
◇ Waves glossary▸ Simple Harmonic MotionWavelength λII · Waves
one spatial cycle.0 · Basics, phase & sign convention
◇ Waves glossary▸ Waves and SoundWheatstone bridgeV · Electromagnetism
Wheatstone bridge balances at P/Q = R/S — the galvanometer reads zero.4 · Electric current in conductors
◇ Electromagnetism glossary● Current ElectricityWien's displacement lawIII · Thermodynamics
the emission peak shifts to shorter wavelength as a body heats: hotter looks bluer.6 · Heat transfer
◇ Thermodynamics glossary● Thermal Properties of MatterWork function φVI · Modern Physics
least energy to free an electron; emission needs ν ≥ ν₀ regardless of intensity.01 · Photoelectric Effect & Dual Nature
◇ Modern Physics glossary▸ Dual Nature of Radiation and MatterWork in a gas processIII · Thermodynamics
W = ∫P dV is the area under the P–V (indicator) curve; positive on expansion.4 · Laws of thermodynamics
◇ Thermodynamics glossary● The Laws of ThermodynamicsWork ΔWIII · Thermodynamics
+ when done BY the gas (expansion), − on compression.0 · Conventions & the first law
◇ Thermodynamics glossary● The Laws of ThermodynamicsWork–energy theoremI · Mechanics
the net work of all forces equals the change in kinetic energy.08 · Work & Energy
◇ Mechanics glossary▸ Work, Energy and PowerZ
1 termsZeroth law of thermodynamicsIII · Thermodynamics
bodies in thermal equilibrium share one temperature — what a thermometer reads.0 · Conventions & the first law
◇ Thermodynamics glossary▸ The Laws of ThermodynamicsNothing here is written twice: every definition is the one already in its Part glossary, and every link goes to the chapter that earns it. Concept traps does the same job for mistakes; chapter banks for questions.