Nuclear and Particle Physics covers radioactivity and exponential decay, mass-energy equivalence, fission and fusion, the Standard Model of particle physics, and quantum phenomena like the photoelectric effect and wave-particle duality.
Radioactive decay: random and spontaneous. Activity A = λN (λ = decay constant). Half-life t₁/₂ = ln2/λ. Exponential decay: N = N₀e^(−λt), A = A₀e^(−λt). Alpha, beta-minus, beta-plus, gamma decay. Nuclear equations: conserve mass number A and atomic number Z. Mass-energy equivalence: E = mc². Mass defect Δm: difference between mass of individual nucleons and nucleus. Binding energy = Δmc². Binding energy per nucleon: peaks around Fe-56 (most stable). Fission: heavy nuclei split → lighter nuclei + neutrons + energy. Chain reaction. Fusion: light nuclei join → heavier nucleus + energy. Powers stars. Requires extreme temperature (kinetic energy to overcome Coulomb repulsion).
Particles: hadrons (made of quarks — baryons like proton/neutron have 3 quarks, mesons have quark-antiquark), leptons (electrons, neutrinos — not made of quarks). Quarks: up (+2/3e), down (−1/3e), strange, charm, top, bottom. Antiquarks: opposite charge. Conservation laws: charge, baryon number, lepton number, strangeness (in strong interactions). Exchange particles (gauge bosons): photon (EM), W±/Z⁰ (weak), gluon (strong). Photoelectric effect: light as photons, E = hf. Work function φ: KEₘₐₓ = hf − φ. Threshold frequency f₀ = φ/h. Wave-particle duality: de Broglie wavelength λ = h/p = h/(mv). Electron diffraction demonstrates wave nature. Energy levels: atoms have discrete levels. Photon emitted/absorbed: E = hf = E₂ − E₁. Line spectra as evidence.
Wave-particle duality is the concept that all particles exhibit both wave and particle properties, and all waves exhibit both properties too. For light: the photoelectric effect shows particle behaviour (photons with energy E = hf), while diffraction and interference show wave behaviour. For electrons: electron diffraction through a thin graphite film produces ring patterns typical of waves, demonstrating their wave nature. The de Broglie wavelength λ = h/p = h/(mv) links the two: faster particles have shorter wavelengths. At everyday scales, objects have wavelengths too small to observe. At atomic scales, wave behaviour dominates. This duality is fundamental to quantum mechanics — things aren\'t "either wave or particle" but exhibit both, depending on the experiment. The uncertainty principle follows from this: you cannot simultaneously know exact position and momentum.
Book a Trial + Diagnostic session. Get a personalized Learning Path with clear milestones, tutor match, and a plan recommendation — all within 24 hours.
Book Trial + Diagnostic →