DZI Physics and Astronomy study guide
DZI Physics and Astronomy · Work through your exam, one topic at a time.
The DZI Physics and Astronomy credential is a multiple-choice assessment designed to test whether a candidate commands the core physics that underpins astronomical reasoning, from Newtonian mechanics through cosmology. It suits candidates preparing for graduate study or technical work in astronomy, physics teaching, science communication, or data-heavy research support, and it is also useful for self-directed learners who want an external check on breadth rather than depth in a single subfield. The DZI Physics and Astronomy study guide has 9 sections and about 2,442 words.
01Mechanics and Gravitation
Newton's three laws underpin everything here: inertia, F = ma as a vector relation, and action–reaction pairs acting on different bodies. Extend to work–energy (work is the line integral of force; conservative forces admit a potential), impulse–momentum (J = Δp), and conservation laws, which are the fastest route through most problems.
292 words, about 1 min02Thermodynamics and Statistical Physics
Know the first law ΔU = Q − W (sign conventions matter) and the second law in both Kelvin–Planck and Clausius forms. Entropy change is ΔS = ∫dQ rev/T, and irreversibility means ΔS universe ≥ 0.
289 words, about 1 min03Waves, Optics, and Acoustics
Wave fundamentals: v = fλ, superposition, and the distinction between transverse and longitudinal waves. Sound intensity follows the inverse-square law and decibels use 10 log₁₀(I/I₀), with I₀ = 10⁻¹² W/m².
287 words, about 1 min04Electricity and Magnetism
Electrostatics: Coulomb's law, electric field E = F/q, Gauss's law (flux = Q enc/ε₀), and potential V with E = −dV/dx. Capacitance C = Q/V, energy ½CV², and dielectrics multiplying C by κ.
272 words, about 1 min05Quantum Mechanics and Atomic Physics
Wave–particle duality, the de Broglie relation λ = h/p, and the photoelectric effect with E = hf and work function φ. The uncertainty principle ΔxΔp ≥ ℏ/2 limits simultaneous knowledge.
267 words, about 1 min06Relativity and Modern Physics
Special relativity rests on two postulates: physics is the same in all inertial frames, and light speed is invariant. Consequences: time dilation Δt = γΔt₀, length contraction L = L₀/γ, and the Lorentz factor γ = 1/√(1 − v²/c²).
294 words, about 1 min07Astrophysics and Stellar Structure
Stellar structure balances hydrostatic equilibrium (pressure gradient versus gravity), energy transport (radiative and convective), and nuclear fusion in the core. The Hertzsprung–Russell diagram plots luminosity against temperature; the main sequence runs from hot, luminous O stars to cool, dim M dwarfs.
248 words, about 1 min08Cosmology and Galactic Astronomy
Hubble's law v = H₀d describes cosmic expansion; redshift z = (λ obs − λ em)/λ em and v ≈ cz for low z. The Friedmann equations connect expansion rate to density and curvature.
250 words, about 1 min09Experimental Methods, Data Analysis, and Measurement
Measurement uncertainty: distinguish random from systematic errors, report results with uncertainty and units, and use significant figures correctly. Combine independent uncertainties in quadrature: for z = x + y, σ z = √(σ x² + σ y²); for products, fractional uncertainties add in quadrature.
243 words, about 1 min