IB DP Physics HL Study Notes

First Assessment 2025

A. Space, Time and Motion

A.1 Kinematics (with HL Extensions)

• Linear Kinematics: Vector vs scalar definitions. Position, displacement, distance, velocity, speed, acceleration. Equations of uniformly accelerated motion (suvat). Projectile motion (independence of vertical and horizontal motion) and fluid resistance (terminal velocity).
• HL: Rotational Kinematics: Angular displacement (θ), angular velocity (ω), angular acceleration (α). Equations of uniformly accelerated rotational motion correspond directly to linear motion equations (e.g., ω = ω₀ + αt). Tangential and centripetal components of acceleration.

A.2 Forces and Momentum (with HL Extensions)

• Core Mechanics: Newton's three laws, translational equilibrium. Types of forces (Weight, Normal, Friction, Tension, Hooke's Law, Buoyancy, Viscous drag). Linear momentum (p=mv) and Impulse (J=FΔt). Conservation of momentum in elastic and inelastic collisions. Circular motion (centripetal force).
• HL: Rigid Body Mechanics: Torque (τ = rF sin θ or τ = Iα). Moment of inertia (I). Rotational equilibrium (net torque = 0). Angular momentum (L = Iω) and its conservation. Couples and center of mass.

A.3 Work, Energy and Power (with HL Extensions)

• Core Energy: Work done (W = Fscosθ). Mechanical energy (kinetic, gravitational potential, elastic potential). Conservation of energy, Power, and Efficiency.
• HL: Rotational Work and Energy: Rotational kinetic energy (E_k = ½ Iω²). Work done by a torque (W = τθ). Rolling without slipping involves both translational and rotational kinetic energy.

A.4 Galilean and Special Relativity (HL Only)

• Reference Frames: Galilean relativity and transformations. Inertial vs non-inertial frames.
• Postulates of Special Relativity: The speed of light in a vacuum is the same for all inertial observers. The laws of physics are the same in all inertial reference frames.
• Relativistic Effects: Time dilation (moving clocks run slower: Δt = γΔt₀). Length contraction (moving objects are shorter in the direction of motion: L = L₀ / γ).
• Spacetime: Lorentz transformations. Spacetime diagrams (Minkowski diagrams), worldlines, simultaneity, and the invariant spacetime interval.

B. The Particulate Nature of Matter

B.1 - B.3 Thermal Energy, Greenhouse Effect, and Gas Laws

• Core: Kinetic theory, internal energy, phase changes, specific heat (Q=mcΔT), latent heat (Q=mL). Conduction, convection, radiation (Wien's Law, Stefan-Boltzmann). Albedo, emissivity, and the Greenhouse Effect. Ideal Gas Law (PV=nRT) and the kinetic model of an ideal gas.

B.4 Thermodynamics (HL Only)

• First Law of Thermodynamics: Q = ΔU + W. Energy conservation in thermodynamic systems.
• Thermodynamic Processes: Isobaric (constant pressure), Isochoric/Isovolumetric (constant volume), Isothermal (constant temperature, ΔU = 0), Adiabatic (no heat exchange, Q = 0, PV^5/3 = constant for monatomic ideal gas).
• PV Diagrams: Work done is the area under the curve. Cyclic processes.
• Second Law and Entropy: Heat flows naturally from hot to cold. Entropy is a measure of disorder; total entropy of an isolated system always increases. Carnot cycle and maximum theoretical efficiency.

B.5 Current and Circuits

• Core: Direct current, potential difference, resistance, Ohm's law, electrical power. Series and parallel circuits, internal resistance, and electromotive force (emf). Kirchhoff's laws applied to simple circuits.

C. Wave Behaviour

C.1 Simple Harmonic Motion (with HL Extensions)

• Core: Defining equation (a = -ω²x). Period, frequency, energy interchange in mass-spring and pendulum systems.
• HL: SHM Equations: x = x₀ cos(ωt) or sin(ωt), v = -ωx₀ sin(ωt), v = ±ω√(x₀² - x²). Phase angle. Detailed kinetic and potential energy equations.

C.2 & C.3 Wave Model and Phenomena (with HL Extensions)

• Core: Transverse/longitudinal waves, wave equation (v=fλ). Reflection, refraction (Snell's law), superposition, interference (Young's double slit).
• HL: Single Slit Diffraction: Intensity pattern, width of the central maximum (θ = λ/b).
• HL: Interference and Resolution: Multiple slit interference and diffraction gratings (nλ = d sin θ). Rayleigh criterion for resolution (θ = 1.22λ / b for circular apertures). Resolving power of gratings (R = λ / Δλ = mN).

C.4 Standing Waves and Resonance

• Core & HL: Nodes and antinodes. Harmonics in strings and pipes (open/closed). Resonance and the effects of damping on the amplitude-frequency graph.

C.5 Doppler Effect (with HL Extensions)

• Core: Conceptual understanding for sound and light (redshift/blueshift).
• HL: Doppler Equations for Sound: Moving source (f' = f [v / (v ± u_s)]) and moving observer (f' = f [(v ± u_o) / v]).

D. Fields

D.1 & D.2 Gravitational, Electric and Magnetic Fields (with HL Extensions)

• Core: Newton's law of gravitation (F = GMm/r²), Coulomb's law (F = kq₁q₂/r²). Field strength definitions (g = F/m, E = F/q). Orbital motion.
• HL: Potential and Potential Energy: Gravitational potential (V_g = -GM/r) and Electric potential (V_e = kq/r). Potential energy (E_p = mV_g or qV_e). Potential gradient is the negative of field strength (g = -ΔV/Δr). Equipotential surfaces and their relationship to field lines. Escape speed (v = √(2GM/r)).

D.3 Motion in Electromagnetic Fields

• Core: Magnetic force on a moving charge (F = qvB sin θ) and on a current-carrying wire (F = BIL sin θ). Force between parallel wires.

D.4 Electromagnetic Induction (HL Only)

• Magnetic Flux and Linkage: Φ = BA cos θ.
• Faraday's and Lenz's Laws: ε = -N (ΔΦ / Δt). Induced emf opposes the change in flux that produced it.
• Alternating Current (AC): AC generators, root mean square (rms) values (I_rms = I₀ / √2, V_rms = V₀ / √2). Transformers (V_p/V_s = N_p/N_s) and power transmission losses.
• Rectification and Smoothing: Diode bridges for half-wave and full-wave rectification. Use of capacitors for smoothing.
• Capacitors: Capacitance (C = q/V), dielectrics, energy stored (E = ½ CV²). Discharging/Charging equations (q = q₀ e^-t/RC), time constant (τ = RC).

E. Nuclear and Quantum Physics

E.1 Structure of the Atom (with HL Extensions)

• Core: Rutherford scattering, atomic energy levels, emission/absorption spectra, photon energy.
• HL: Quantum Physics: Photoelectric effect, Einstein's equation (E_max = hf - Φ), stopping potential. Matter waves (de Broglie wavelength λ = h/p).
• HL: Advanced Quantum Models: Bohr model limitations. The Schrödinger wave function (probability density). Heisenberg's Uncertainty Principle (ΔxΔp ≥ h/4π, ΔEΔt ≥ h/4π).

E.3 Radioactive Decay (with HL Extensions)

• Core: Mass defect and binding energy (E = mc²), strong nuclear force. Alpha, beta, gamma decay. Half-life concept.
• HL: Decay Law: Exponential decay equation (N = N₀ e^-λt). Activity (A = λN). Relationship between half-life and decay constant (T_1/2 = ln2 / λ).

E.4 & E.5 Fission, Fusion and Stars

• Core & HL: Spontaneous and induced fission, chain reactions. Fusion conditions in stars, balancing gravitational collapse with radiation pressure. Hertzsprung-Russell (HR) diagrams and stellar evolution (main sequence, giants, white dwarfs, neutron stars, black holes). Stellar parallax for determining distances.