Physics guides
Each guide answers one question the way you would ask it, then shows the work: the formula, the steps, a worked example computed with g = 9.8 m/s² like the AP equation sheet, and the mistakes that cost points.
Fluids in AP Physics 1: Pressure, Buoyancy, BernoulliFluids is Unit 8 of AP Physics 1, worth 10-15% of the multiple-choice section. Pressure vs depth, buoyancy, continuity, and Bernoulli, with worked examples.Centripetal Force and Acceleration, ExplainedCentripetal force is the net inward force in circular motion. Learn the mv^2/r formula, how real forces supply it, and why centrifugal force is a myth.Conservation of Energy: How to Solve Energy ProblemsSolve conservation of energy problems with one equation: initial equals final plus losses. Formulas for K, Ug, and Us, plus worked examples.Conservation of Momentum: Elastic vs Inelastic CollisionsMomentum is conserved in all collisions; kinetic energy only in elastic ones. Formulas, a comparison table, and worked AP Physics 1 examples.Coulomb's Law: Electric Force Between Two ChargesCoulomb's law gives the electric force between two charges: F = kq1q2/r^2 with k = 9.0 x 10^9. Signs, inverse-square scaling, and worked AP examples.Electric Field and Electric Potential of a Point ChargeHow to find the electric field (E = kq/r^2) and potential (V = kq/r) of a point charge, why one is a vector and one is a scalar, with AP worked examples.Gauss's Law Explained with Worked Examples (AP Physics C)Gauss's law for AP Physics C: E&M: electric flux, closed surfaces, symmetry shortcuts, and worked sphere, line, and cube examples with arithmetic.How to Calculate Torque and Solve Rotational EquilibriumTorque is rF sin theta. Learn what the lever arm means, how the sign convention works, and how to set net torque to zero in seesaw and beam problems.How to Draw a Free Body Diagram (Worked Examples)Step-by-step method for drawing free body diagrams, with worked examples on flat ground, inclines, and ropes, plus the mistakes that cost AP points.How to Find the Coefficient of Friction (Static & Kinetic)Find the coefficient of friction with mu = Ff/FN. Covers static vs kinetic friction, the tan theta ramp method, and worked AP Physics 1 examples.How to Find Net Force and Acceleration with F = maFind net force by adding force components with signs, then get acceleration from F = ma. Worked two-force and multi-force AP Physics 1 examples.How to Find Normal Force: Flat Ground, Inclines, ElevatorsNormal force is not always mg. Learn to find it on flat ground, on inclines with N = mg cos(theta), and in accelerating elevators, with worked examples.How to Find Tension in a Rope (Single & Connected Masses)Learn how to find tension in a rope with Newton's second law: hanging masses, horizontal pulls, and two blocks connected by a string, with worked examples.How to Solve Projectile Motion Problems Step by StepSolve projectile motion problems by splitting x and y. Step-by-step recipes for horizontal and angled launches: time of flight, range, max height.Impulse-Momentum Theorem Explained (AP Physics 1)Impulse equals change in momentum: J = Favg Δt = Δp. See three ways to find impulse, how to read force-time graphs, and why airbags cut crash forces.How to Solve Inclined Plane Problems in PhysicsLearn the tilted-axes method for ramps: split gravity into mg sin theta and mg cos theta, run the static friction test, and find the acceleration.Is AP Physics 1 Hard? 2025 Pass Rates and How to PrepareAP Physics 1 pass rates jumped from 47.3% to 67.3% with the redesigned 8-unit course. See why the exam is still hard and how to prepare for it.Kinematic Equations: The 4 Formulas and When to Use EachAll 4 kinematic equations, which one to pick by the missing variable, and why the AP Physics 1 sheet only prints 3. With worked examples using g = 9.8.Ohm's Law: How to Find Current, Voltage & ResistanceLearn Ohm's law for AP Physics 2: I = ΔV/R, all three rearrangements, power P = IΔV, a worked series circuit example, and when a resistor is ohmic.Rotational Kinematics and Moment of Inertia, ExplainedLearn the rotational kinematics equations, moment of inertia, and angular momentum conservation with worked examples for AP Physics 1 Units 5 and 6.Series vs Parallel Circuits: Equivalent ResistanceSeries vs parallel circuits: equivalent resistance rules, what stays constant in each, and a mixed-circuit example with every step shown.Simple Harmonic Motion: Pendulum and Spring PeriodThe spring period is T = 2 pi sqrt(m/k) and the pendulum period is T = 2 pi sqrt(l/g). See what does not affect each, plus energy trades and worked examples.Thermodynamics: PV Diagrams & the First Law (AP Physics 2)Master the AP Physics 2 sign convention: W = -PΔV is work done on the gas and ΔU = Q + W. Read PV diagrams, find work from area, and handle cycles.Wave Speed, Frequency, and Wavelength: How to Find EachUse v = f lambda to solve for wave speed, frequency, or wavelength. Worked examples, T = 1/f, and why only frequency stays fixed in a new medium.Work-Energy Theorem Explained with ExamplesNet work equals the change in kinetic energy. Learn the Fd cos theta sign rules, three worked AP examples, and when to use energy instead of kinematics.