Sachsen-Anhalt Abitur Physics cheat sheet

Resolve vectors before applying F = ma or the SUVAT equations

Momentum is a vector: conserve each component only when the corresponding net external impulse is zero

Equilibrium requires both zero resultant force and zero resultant moment

The centripetal component points to the centre; uniform circular motion has constant speed but changing velocity

SHM signature: a = −ω²x, giving T = 2π/ω

State g and sign conventions explicitly at the start of a solution

EMF is per unit charge from the source; terminal p.d. is E − Ir

Kirchhoff's laws follow from conservation of charge and energy

Capacitor energy is ½CV²; discharge is exponential with time constant RC

Magnetic-force magnitude is |q|vB sinθ and its vector is perpendicular to velocity, so magnetic force does no work

Lenz's law: induced effects oppose the change that causes them

RMS values: I₀/√2 and V₀/√2 for sinusoidal quantities

hf = φ + KEmax; intensity affects rate, not maximum energy

Threshold frequency f₀ = φ/h in the ordinary single-photon model; below it that model predicts no photoemission

hf = E₂ − E₁ explains line spectra

λ = h/p generally; p = mv for a nonrelativistic massive particle

α: A−4, Z−2; β⁻: Z+1; γ: no change in A or Z

N = N₀e^(−λt) with t½ = ln2/λ; 1 u c² is approximately 931.5 MeV

SHM requires a restoring acceleration proportional to minus displacement.

For an ideal mass-spring model, omega = sqrt(k/m) and T = 2pi sqrt(m/k).

Maximum speed is omega A and total energy is kA squared divided by two.

Pendulum period formula requires the small-angle approximation.

Damping removes oscillator energy; a periodic drive can supply energy.

An ideal LC circuit has omega = 1/sqrt(LC).

Phase difference = 2π × path difference/λ

Stationary waves: node spacing λ/2, node–antinode λ/4, no energy transfer

Grating equation d sinθ = nλ with d = 1/N in metres

Young's slits: x = λD/a for small angles

Snell: n₁ sinθ₁ = n₂ sinθ₂; critical angle sinθc = n₂/n₁ requires n₁ > n₂

Keep one lens sign convention throughout and state it

γ = 1/√(1 − v²/c²) ≥ 1.

Dilatación temporal: Δt = γ·Δt₀; contracción: L = L₀/γ.

p = γmv y E = γmc²; E_k = (γ − 1)mc².

E² = p²c² + m²c⁴; para el fotón E = pc.

El tiempo propio se mide en el sistema donde los sucesos ocurren en el mismo lugar.

F = G·M·m/r² y g = G·M/r²; el campo apunta hacia la masa que lo crea.

V = −G·M/r y E_p = −G·M·m/r, con referencia cero en el infinito.

Órbita circular: v = √(G·M/r) y T² = 4π²·r³/(G·M).

Energía mecánica de una órbita circular: E = −G·M·m/(2r).

La velocidad de escape cumple v_e = √(2G·M/R).

State resolution and uncertainty convention for each instrument

Random errors → repeats and means; systematic errors → correction

For first-order worst-case bounds, add relative contributions; independent standard uncertainties use quadrature

Gradient from two points on the best-fit line, with units

Average repeated timings and time many oscillations to cut reaction error

Never quote more significant figures than the data justify

Define whether the boundary is the surface or top of the atmosphere.

Absorbed solar flux equals (1 - albedo) times mean incident solar flux.

A spherical planet introduces a disk-to-surface geometric factor of four.

Positive net incoming flux means energy accumulates in the system.

Blackbody emission scales as absolute temperature to the fourth power.

Greenhouse absorption, albedo and heat transport affect different parts of the budget.