AP® Physics 2: Algebra-Based Cheat Sheet

Master AP Physics 2: Algebra-Based with this cheat sheet from Examples.com. It covers key concepts and formulas in fluids, thermodynamics, circuits, optics, and more, perfect for exam preparation and quick reference.

Free AP Physics 2: Algebra-Based Practice Test

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Unit 1: Fluids

• Density: $\rho = \frac{m}{V}$$\rho = \frac{m}{V}$

  • m = mass, V = volume

• Pressure: P = $\frac{F}{A}$$\frac{F}{A}$​

  • F = force, A = area

• Pascal's Principle: $P₁ = P₂$$P₁ = P₂$​ (Pressure applied at any point in an incompressible fluid is transmitted undiminished)

• Continuity Equation: $A_1v_1 = A_2v_2$$A_1v_1 = A_2v_2$​

  • A = cross-sectional area, v = fluid velocity

• Bernoulli’s Equation: $P_1 + \frac{1}{2}\rho v_1^2 + \rho gh_1 = P_2 + \frac{1}{2}\rho v_2^2 + \rho gh_2$$P_1 + \frac{1}{2}\rho v_1^2 + \rho gh_1 = P_2 + \frac{1}{2}\rho v_2^2 + \rho gh_2$

• Archimedes' Principle: $F_b = \rho_{fluid} \cdot V_{displaced} \cdot g$$F_b = \rho_{fluid} \cdot V_{displaced} \cdot g$

  • $F_b$$F_b$​ = buoyant force

Unit 2: Thermodynamics

• Temperature Conversion:

  • T(K)=T(°C)+273.15

• Ideal Gas Law: PV=nRT

  • P = pressure, V = volume, n = number of moles, R = ideal gas constant, T = temperature

• Kinetic Theory: $\frac{3}{2} k_B T = \frac{1}{2} mv_{rms}^2$$\frac{3}{2} k_B T = \frac{1}{2} mv_{rms}^2$

• First Law of Thermodynamics: ΔU = Q − W

  • Q = heat added, W = work done by the system

• Heat Transfer: Q=mcΔT

  • Q = heat, m = mass, c = specific heat, ΔT = change in temperature

• Heat Engine Efficiency: $\eta = \frac{W_{out}}{Q_{in}}$$\eta = \frac{W_{out}}{Q_{in}}$

Unit 3: Electric Force, Field, and Potential

• Coulomb’s Law: $F_e = k_e \frac{|q_1q_2|}{r^2}$$F_e = k_e \frac{|q_1q_2|}{r^2}$

  • $k_e = 8.99 \times 10^9 \, \text{Nm}^2/\text{C}^2$$k_e = 8.99 \times 10^9 \, \text{Nm}^2/\text{C}^2$

• Electric Field: $E = \frac{F_e}{q} = k_e \frac{|q|}{r^2}$$E = \frac{F_e}{q} = k_e \frac{|q|}{r^2}$

• Electric Potential Energy: $U = k_e \frac{q_1q_2}{r}$$U = k_e \frac{q_1q_2}{r}$

• Electric Potential: $V = \frac{U}{q} = k_e \frac{q}{r}$$V = \frac{U}{q} = k_e \frac{q}{r}$

• Capacitance: $C = \frac{Q}{V}$$C = \frac{Q}{V}$

  • Q = charge, V = voltage

• Parallel Plate Capacitor: $C = \frac{\epsilon_0 A}{d}$$C = \frac{\epsilon_0 A}{d}$

  • $\epsilon_0$$\epsilon_0$ = permittivity of free space, A = area, d = separation between plates

Unit 4: Circuits

• Ohm’s Law: V = IR

  • V = voltage, I = current, R = resistance

• Resistors in Series: $R_{eq} = R_1 + R_2 + \cdots$$R_{eq} = R_1 + R_2 + \cdots$

• Resistors in Parallel: $\frac{1}{R_{eq}} = \frac{1}{R_1} + \frac{1}{R_2} + \cdots$$\frac{1}{R_{eq}} = \frac{1}{R_1} + \frac{1}{R_2} + \cdots$

• Power: $P = IV = I^2R = \frac{V^2}{R}$$P = IV = I^2R = \frac{V^2}{R}$

• Kirchhoff’s Rules:

  • Junction Rule: $\sum I_{in} = \sum I_{out}$$\sum I_{in} = \sum I_{out}$

  • Loop Rule: $\sum \Delta V = 0$$\sum \Delta V = 0$

• Capacitors in Series: $\frac{1}{C_{eq}} = \frac{1}{C_1} + \frac{1}{C_2} + \cdots$$\frac{1}{C_{eq}} = \frac{1}{C_1} + \frac{1}{C_2} + \cdots$

• Capacitors in Parallel: $C_{eq} = C_1 + C_2 + \cdots$$C_{eq} = C_1 + C_2 + \cdots$

Unit 5: Magnetism & Electromagnetic Induction

• Magnetic Force on a Charge: $F_B = qvB \sin \theta$$F_B = qvB \sin \theta$

  • q = charge, v = velocity, B = magnetic field

• Magnetic Force on a Wire: $F_B = ILB \sin \theta$$F_B = ILB \sin \theta$

  • I = current, L = length of wire, B = magnetic field

• Ampère’s Law: $\oint \vec{B} \cdot d\vec{l} = \mu_0 I_{enc}$$\oint \vec{B} \cdot d\vec{l} = \mu_0 I_{enc}$

• Faraday's Law: $\mathcal{E} = -\frac{d\Phi_B}{dt}$$\mathcal{E} = -\frac{d\Phi_B}{dt}$

  • $\Phi_B$$\Phi_B$​ = magnetic flux

• Lenz's Law: The induced emf always opposes the change in magnetic flux

• Inductance: $V = L \frac{dI}{dt}$$V = L \frac{dI}{dt}$

Unit 6: Geometric & Physical Optics

• Snell’s Law: $n_1 \sin \theta_1 = n_2 \sin \theta_2$$n_1 \sin \theta_1 = n_2 \sin \theta_2$

  • n = refractive index

• Lens/Mirror Equation: $\frac{1}{f} = \frac{1}{d_o} + \frac{1}{d_i}$$\frac{1}{f} = \frac{1}{d_o} + \frac{1}{d_i}$

  • f = focal length, $d_o$$d_o$​ = object distance, $d_i$$d_i$​ = image distance

• Magnification: $M = -\frac{d_i}{d_o}$$M = -\frac{d_i}{d_o}$

• Critical Angle: $\sin \theta_c = \frac{n_2}{n_1}$$\sin \theta_c = \frac{n_2}{n_1}$​​ (for total internal reflection)

• Young's Double-Slit Experiment:

  • $x = \frac{\lambda L}{d}$$x = \frac{\lambda L}{d}$

    • x = fringe spacing, $\lambda$$\lambda$ = wavelength, L = distance to screen, d = slit separation

• Diffraction Grating: $d \sin \theta = m\lambda d$$d \sin \theta = m\lambda d$

  • mmm = order of diffraction

Unit 7: Quantum, Atomic, & Nuclear Physics

• Photon Energy: $E = hf = \frac{hc}{\lambda}$$E = hf = \frac{hc}{\lambda}$

  • $h = 6.626 \times 10^{-34}$$h = 6.626 \times 10^{-34}$ J·s (Planck's constant)

• Photoelectric Effect: $K_ₘₐₓ =

  • $\phi$$\phi$ = work function

• de Broglie Wavelength: $\lambda = \frac{h}{p}$$\lambda = \frac{h}{p}$

  • ppp = momentum

• Heisenberg Uncertainty Principle: $\Delta x \cdot \Delta p \geq \frac{h}{4\pi}$$\Delta x \cdot \Delta p \geq \frac{h}{4\pi}$​

• Radioactive Decay:

  • $N(t) = N_0 e^{-\lambda t}$$N(t) = N_0 e^{-\lambda t}$

  • $\lambda = \text{decay constant}$$\lambda = \text{decay constant}$

• Mass-Energy Equivalence: $E = mc^2$$E = mc^2$

FRQ Tips

• Show All Work: Even if the final answer is incorrect, partial credit can be given for correct procedures.

• Use Units: Always include units in your answers.

• Simplify Expressions: If you're stuck, simplify the problem using symmetry or limiting cases.

• Graph Sketching: For graph-based questions, label axes, and indicate critical points like maximums, minimums, and intercepts.

• Equation Manipulation: Keep track of all variables and constants during equation manipulation to avoid mistakes.