The 200-word examination instruction list
AP Physics C: Mechanics asks you to translate a physical model into calculus and explain what the result means. Choose the system and sign convention before differentiating or integrating.
Start with the list or jump to exam requirements, worked examples, the Fencing Method or practice. The list combines task verbs with subject terms that help you interpret the question.
Essential instructions
| No. | Instruction or term | Meaning or action |
|---|---|---|
| 1 | Identify | Name or pick out the item the question specifies. |
| 2 | State | Express the required point directly and clearly. |
| 3 | Describe | Report the relevant characteristics, events or pattern. |
| 4 | Explain | Connect the result to its cause, mechanism or reasoning. |
| 5 | Compare | Set the items side by side on the same relevant feature. |
| 6 | Interpret | Say what a statement, result or display means in context. |
| 7 | Justify | Give evidence for the claim and explain how that evidence supports, qualifies or defends it. |
| 8 | Evaluate | Weigh relevant evidence or criteria before reaching a judgment. |
| 9 | Determine | Work from the given information to establish an answer. |
| 10 | Calculate | Use numbers or other given information to work out a result. |
| 11 | Estimate | Find an approximate answer using the available clues. |
| 12 | Sketch | Show the required shape, relationships and labels. |
| 13 | Construct | Produce the specified representation using the information given. |
| 14 | Label | Attach the correct name to the indicated part. |
| 15 | Select | Choose only the number of options requested. |
| 16 | Check | Test the answer against the original instruction or condition. |
| 17 | Analyze | Break the information into relevant parts and explain how they relate. |
| 18 | Multiple-choice question | Select the answer that satisfies the full stem and any limiting words. |
| 19 | Free-response question | Produce your own answer and complete each labelled task. |
| 20 | Stimulus | Use the figure, extract or other material attached to the question. |
| 21 | Answer each subpart | Treat each lettered instruction as a separate job. |
| 22 | Hybrid digital | Check which questions are displayed digitally and which answers go in a paper booklet. |
Subject terms and physical models
| No. | Instruction or term | Meaning or action |
|---|---|---|
| 23 | Differentiate position | Find instantaneous velocity from the time derivative of position. |
| 24 | Differentiate velocity | Find instantaneous acceleration from the time derivative of velocity. |
| 25 | Integrate acceleration | Find velocity change from the signed time integral. |
| 26 | Integrate velocity | Find displacement from the signed time integral. |
| 27 | Integrate speed | Find total distance from the time integral of velocity magnitude. |
| 28 | Initial condition | Use the stated starting position or velocity to fix the integration constant. |
| 29 | Variable force | Write the force as a function of the relevant coordinate, speed or time. |
| 30 | Work integral | Integrate the component of force along the displacement path. |
| 31 | Potential from force | Integrate the negative of the conservative force component over position. |
| 32 | Force from potential | Take the negative spatial derivative of potential energy in one dimension. |
| 33 | Conservative force | Identify a force whose work between two points does not depend on the path. |
| 34 | Stable equilibrium | Identify a local minimum of potential energy in the one-dimensional model. |
| 35 | Unstable equilibrium | Identify a local maximum of potential energy in the one-dimensional model. |
| 36 | Turning point | Find where kinetic energy vanishes and the direction of motion reverses. |
| 37 | Instantaneous power | Use the dot product of force and velocity for the power delivered by that force. |
| 38 | Impulse integral | Integrate net force over the specified time interval. |
| 39 | Momentum derivative | Relate net external force to the time rate of change of momentum. |
| 40 | Centre-of-mass velocity | Divide total momentum by the system’s total mass. |
| 41 | Continuous mass distribution | Represent small mass elements using the density and appropriate length, area or volume element. |
| 42 | Linear mass density | Express mass per unit length and integrate when density varies. |
| 43 | Centre-of-mass integral | Integrate position times mass element and divide by total mass. |
| 44 | Moment-of-inertia integral | Integrate squared distance from the chosen axis over mass. |
| 45 | Parallel-axis theorem | Add mass times squared axis separation to the centre-of-mass moment of inertia. |
| 46 | Torque integral | Sum torques from distributed forces about a specified axis using an integral. |
| 47 | Angular impulse | Integrate net torque over time to find angular momentum change. |
| 48 | Angular momentum of a particle | Take the cross product of position relative to the origin and linear momentum. |
| 49 | Work by torque | Integrate torque about a fixed axis over angular displacement. |
| 50 | Rolling constraint | Relate translation and rotation for motion without slipping. |
| 51 | Static-friction direction | Determine which relative sliding would occur without friction and oppose that tendency. |
| 52 | Drag force | Model resistance as a function of speed with direction opposite relative motion through the medium. |
| 53 | Terminal speed | Find the speed where drag balances the other forces along the motion. |
| 54 | Differential equation of motion | Translate Newton’s law into an equation involving derivatives and solve or analyse it with initial conditions. |
| 55 | Sinusoidal solution | Match amplitude, angular frequency and phase to the equation and starting values. |
| 56 | Angular frequency | Use radians per unit time, equal to 2π divided by the period for periodic motion. |
| 57 | Small-angle approximation | Use sin θ approximately equal to θ in radians when the angle is small. |
| 58 | Simple pendulum period | Use the small-angle model and identify pendulum length and gravitational acceleration. |
| 59 | Effective spring constant | Relate the net restoring force to displacement near equilibrium. |
| 60 | Inverse-square gravitation | Find gravitational force from masses and inverse squared separation. |
| 61 | Gravitational potential energy | For two point masses use −GMm/r with zero chosen at infinite separation. |
| 62 | Circular-orbit speed | Set gravitational force equal to the required inward net force for a circular orbit. |
| 63 | Escape speed | Set the minimum energy for reaching infinity with zero remaining speed in the isolated model. |
| 64 | Orbital period | Relate the orbital circumference and speed for a circular orbit. |
| 65 | Dimensional check of an integral | Multiply the integrand’s units by the integration variable’s units. |
| 66 | Translate a graph into an integral | Identify the signed area and the physical quantity it represents. |
| 67 | Compare differential and integral forms | State whether the question asks for a local rate or a change over an interval. |
Representations, experiments and calculations
| No. | Instruction or term | Meaning or action |
|---|---|---|
| 68 | Choose a system | State which objects are included before applying a force, energy or momentum relationship. |
| 69 | Free-body diagram | Draw and label the forces acting on the specified object or system. |
| 70 | Net force | Find the vector sum of external forces on the selected system. |
| 71 | Resultant acceleration | Use the direction and magnitude of net force per unit mass. |
| 72 | Inertial reference frame | Use a frame in which a force-free object moves at constant velocity. |
| 73 | Displacement | Give the signed or vector change in position. |
| 74 | Velocity | Give the rate of position change with direction. |
| 75 | Speed | Give the magnitude of velocity. |
| 76 | Acceleration | Give the rate of velocity change with direction. |
| 77 | Constant acceleration | Use kinematics relationships only where acceleration is constant. |
| 78 | Position–time graph | Use the slope to find velocity at the requested time or interval. |
| 79 | Velocity–time graph | Use slope for acceleration and signed area for displacement. |
| 80 | Acceleration–time graph | Use signed area to find change in velocity. |
| 81 | Projectile motion | Treat horizontal and vertical components separately with a shared time. |
| 82 | Relative velocity | Find velocity with respect to the frame or object named in the question. |
| 83 | Weight | Use the gravitational force on the object, with direction toward the source. |
| 84 | Normal force | Draw the contact force perpendicular to the supporting surface. |
| 85 | Tension | Draw the pulling force along a taut cord or similar connector. |
| 86 | Static friction | Use the value needed to prevent sliding up to its maximum. |
| 87 | Kinetic friction | Draw friction opposite relative sliding at the contact. |
| 88 | Force pair | Identify equal and opposite interaction forces on different objects. |
| 89 | Translational equilibrium | Set the net force to zero for the system. |
| 90 | Uniform circular motion | Track changing velocity direction even though speed stays constant. |
| 91 | Centripetal acceleration | Find inward acceleration from speed squared divided by radius. |
| 92 | Radial direction | Resolve the quantity along the line from the centre of rotation. |
| 93 | Tangential direction | Resolve along the tangent perpendicular to the radial direction. |
| 94 | Work | Find energy transferred by a force acting through displacement. |
| 95 | Work–energy theorem | Relate total work on an object to its change in kinetic energy. |
| 96 | Kinetic energy | Use one-half mass times speed squared for translational motion. |
| 97 | Elastic potential energy | For an ideal spring, use one-half spring constant times displacement squared. |
| 98 | Mechanical energy | Add the kinetic and applicable potential energies of the system. |
| 99 | Energy transfer | Account for energy crossing the system boundary. |
| 100 | Conservation of energy | Account for energy within the system and transfers across its boundary. |
| 101 | Power | Find the rate at which energy is transferred or work is done. |
| 102 | Momentum | Multiply mass by velocity and keep track of direction. |
| 103 | Impulse | Use net force integrated over time, or the momentum change. |
| 104 | Force–time graph | Find impulse from the signed area under the net-force curve. |
| 105 | Conservation of momentum | Set initial and final total momentum equal when net external impulse is negligible. |
| 106 | Elastic collision | Use conservation of kinetic energy as well as the appropriate momentum condition. |
| 107 | Inelastic collision | Allow total kinetic energy to change while checking the momentum condition. |
| 108 | Perfectly inelastic collision | Assign a shared final velocity to objects that stick together. |
| 109 | Centre of mass | Locate the mass-weighted average position of the system. |
| 110 | Torque | Use the lever arm and force to find the turning effect about a chosen axis. |
| 111 | Lever arm | Find the perpendicular distance from the axis to the force’s line of action. |
| 112 | Angular displacement | Give the signed change in angle. |
| 113 | Angular velocity | Find the rate of change of angular position. |
| 114 | Angular acceleration | Find the rate of change of angular velocity. |
| 115 | Rotational inertia | Account for mass distribution relative to the specified rotation axis. |
| 116 | Rotational equilibrium | Set net torque about the chosen axis to zero. |
| 117 | Rotational kinetic energy | Use one-half rotational inertia times angular speed squared. |
| 118 | Angular momentum | For a rigid body rotating about a fixed axis, use rotational inertia times angular velocity. |
| 119 | External torque | Identify a turning effect produced by an interaction across the system boundary. |
| 120 | Rolling without slipping | Relate centre-of-mass speed to radius times angular speed. |
| 121 | Period | Find the time for one complete cycle. |
| 122 | Frequency | Find the number of cycles per unit time. |
| 123 | Amplitude | Find the greatest displacement from equilibrium. |
| 124 | Restoring force | Identify a force component directed back toward equilibrium. |
| 125 | Simple harmonic motion | Check that acceleration is proportional to displacement and opposite in direction. |
| 126 | Spring constant | Use the proportionality between force magnitude and displacement for an ideal spring. |
| 127 | Hydrostatic pressure | Use fluid density, gravitational field strength and depth to find the pressure increase. |
| 128 | Fluid at rest | Use the hydrostatic pressure relation and buoyancy instead of a flow model. |
| 129 | Vector component | Project the vector onto the named coordinate axis with the correct sign. |
| 130 | Sign convention | State which direction is positive and use it consistently. |
| 131 | Scale drawing | Use the requested scale when converting between arrow length and vector magnitude. |
| 132 | Ranking task | Order the listed cases and show equal rankings where warranted. |
| 133 | Translate a representation | Preserve the physical relationships when switching between words, equations, diagrams and graphs. |
| 134 | Linearise data | Choose transformed axes that yield a straight-line relationship for the proposed model. |
| 135 | Qualitative prediction | State how the outcome changes and give a physical reason. |
| 136 | Quantitative translation | Use the mathematical relationship to connect a numerical result with a qualitative claim. |
| 137 | Experimental design and analysis | Give a repeatable method, then explain how its measurements test the relationship. |
| 138 | Mathematical routine | Build the algebra from a relevant principle and show how it answers the prompt. |
| 139 | Hypothesis | State a testable prediction about a relationship. |
| 140 | Research question | Specify the focused question that the investigation will answer. |
| 141 | Independent variable | Identify what the investigator changes deliberately. |
| 142 | Dependent variable | Identify the measured outcome of the investigation. |
| 143 | Controlled variable | Identify a factor kept constant to help isolate the tested relationship. |
| 144 | Control group | Use the baseline comparison to interpret the treatment effect. |
| 145 | Experimental design | Use the stated groups, conditions and measurements to judge the experiment. |
| 146 | Sample size | Check how many observations, individuals or trials contribute to the result. |
| 147 | Representative sample | Check whether the selected cases reflect the population of interest. |
| 148 | Raw data | Use the measurements as originally collected. |
| 149 | Processed data | Use values calculated, combined or transformed from the original readings. |
| 150 | Outlier | Identify an observation unusually far from the general pattern. |
| 151 | Uncertainty | State or interpret the estimated doubt associated with a measurement or value. |
| 152 | Error bars | Read their meaning from the figure legend before interpreting them. |
| 153 | Repeatability | Consider agreement when the same method is repeated under the same conditions. |
| 154 | Reproducibility | Consider whether results agree when the method is repeated under changed conditions. |
| 155 | Validity | Consider whether the evidence or method answers the intended question. |
| 156 | Reliability | Consider whether a result or method gives consistent findings. |
| 157 | Confounding factor | Identify a factor that could contribute to the apparent relationship. |
| 158 | Operational definition | Use the measurable rule the study gives for the concept. |
| 159 | Correlation | Describe how variables vary together within the data. |
| 160 | Causation | Explain how one factor produces a change in another when evidence supports it. |
| 161 | Trend | The broad direction or pattern over a range. |
| 162 | Pattern | A regularity visible across observations or examples. |
| 163 | Scatterplot | Describe form, direction, strength and unusual points when relevant. |
| 164 | Line of best fit | Draw a line representing the overall pattern of plotted data. |
| 165 | Interpolate | Estimate within the range covered by the data. |
| 166 | Extrapolate | Estimate outside the observed range using an assumed pattern. |
| 167 | Read the axes | Identify the quantities, units and intervals on a graph before using a value. |
| 168 | Gradient from a graph | Calculate change in the vertical quantity per change in the horizontal quantity. |
| 169 | Area under a graph | Use the area only where the graph’s quantities make it the requested accumulated value. |
| 170 | Baseline measurement | Use the reading taken before the stated intervention or change. |
| 171 | Identify the reference group | Find the comparison used to isolate the change attributed to the intervention. |
| 172 | Explain a limitation | Identify the assumption or data issue that restricts the conclusion. |
| 173 | Keep the comparison fair | Compare quantities on the same stated basis and units. |
| 174 | Control treatment | Use the treatment intended to provide a reference comparison. |
| 175 | Residual | Subtract the predicted response from the observed response. |
| 176 | Significant figures | Give the requested number of meaningful digits. |
| 177 | Decimal places | Count the required digits to the right of the decimal point. |
| 178 | Dimensional analysis | Track units through the calculation to see whether the result has the requested dimension. |
| 179 | Order of magnitude | Estimate the relevant power-of-ten scale. |
| 180 | Calculate the percentage change | Divide the change by the starting value and multiply by 100. |
| 181 | Rate of change | Find the change in one quantity per unit change in another. |
| 182 | Unit rate | Calculate the amount corresponding to one unit of the other quantity. |
| 183 | Parameter | Use the fixed or adjustable quantity that defines a family of cases. |
| 184 | Model | Use a simplified mathematical or conceptual representation to address the task. |
| 185 | Table | Information arranged in rows and columns. |
| 186 | Graph | A visual display of data or a mathematical relationship. |
| 187 | Diagram | A drawing showing features, structure or relationships. |
| 188 | Scale | The intervals or measurement relationship used in a display. |
| 189 | Unit | The standard attached to a measurement, such as minutes or metres. |
| 190 | Unit conversion | Use a conversion factor to change the units while keeping the quantity the same. |
| 191 | Interpret the slope | Give the predicted change in response per one unit increase in the explanatory variable. |
| 192 | Interpret the intercept | Explain the predicted response at zero if zero makes sense in context. |
| 193 | Exact value | Leave the answer in a form that preserves its full value. |
| 194 | Give units | Attach the required measurement unit to the final result. |
| 195 | Find the exact value | Retain radicals, fractions, logarithms or π in exact form where appropriate. |
| 196 | Set up an equation | Translate the given conditions into a mathematical relationship. |
| 197 | Check the solution | Substitute the result into the original equation to verify it. |
| 198 | In terms of | Use the specified quantity or symbol in the final expression. |
| 199 | Solve | Find the values that satisfy the equation or inequality. |
| 200 | Substitute | Replace a variable with the given value or expression. |
What the AP Physics C: Mechanics exam requires
College Board lists the regular 2027 exam for May 3. The exam is hybrid digital. Answer multiple-choice items in Bluebook and read the free-response prompts there. Handwrite the free responses in the supplied booklet.
| Exam component | Format and weighting |
|---|---|
| I · Multiple choice | 42 questions in 85 minutes, worth 50%. Expect standalone items and sets that use shared information. |
| II · Free response | 4 questions in 95 minutes, worth 50%. Tasks cover mathematical routines, translation between representations, experimental design and analysis, and translation between qualitative and quantitative descriptions. |
| Calculator policy | Both sections allow approved four-function, scientific or graphing calculators. Bluebook provides scientific and graphing Desmos calculators. |
Use the May 2027 timing when building a mock exam. In graph and experiment tasks, match the diagram or measurement plan to the particular relationship named in the prompt.
AP is a U.S.-based programme taken domestically and internationally. Confirm local reporting time and registration with your school or test centre. Practise with the official materials for your course and exam year.
Read the task before choosing a method
Write the governing principle before substituting. The derivative of position is a local rate, while the integral of velocity over time is a signed displacement. In rotational questions, identify the reference axis before writing a moment of inertia or torque.
Worked examples for common exam instructions
Differentiate to find acceleration
Prompt. For x(t) = 2t³ − 3t in SI units, find the acceleration at t = 2 s.
Answer. Velocity is 6t² − 3. Differentiating again gives acceleration 12t, so the acceleration is +24 m/s².
Integrate a variable force
Prompt. A force F(x) = 4x N acts in the positive x direction as an object moves from 0 to 3 m. Find the work.
Answer. Integrate 4x from 0 to 3. The result is 2x² evaluated at the bounds, or 18 J.
Determine a moment of inertia
Prompt. Set up and evaluate the moment of inertia of a uniform rod of mass M and length L about a perpendicular axis through one end.
Answer. Let x run from 0 to L and use dm = (M/L) dx. Integrating x² dm gives ML²/3.
Design and analyse a spring experiment
Prompt. Describe how to estimate a spring constant from periods measured with different attached masses.
Answer. Measure several oscillations for each mass, then calculate the period. Plot T² versus mass. In the ideal model the slope is 4π²/k, so k is 4π² divided by the fitted slope. Keep oscillations small and use the same spring.
Use the Fencing Method to build an answer
Start with a small, accurate response. Add the detail that fixes it to the question, then add the reason that connects them. Test the explanation on a new case.
Start. Speed increases.
Add context. The velocity and acceleration both point in the positive direction.
Add reasoning. Because the velocity and acceleration have the same sign, acceleration increases the magnitude of velocity.
Transfer. Reverse the velocity while keeping acceleration positive and reassess the speed.
Practise with the 200 terms
Choose one calculation, one graph task and one explanation. Mark where the response identifies the quantity or relationship, provides the requested representation and explains the result. Change one condition and try again.
Distinguish displacement from distance
Try it. Velocity is −2 m/s for 2 s and +3 m/s for 2 s. Find displacement and distance.
Check. Displacement is −4 + 6 = +2 m. Distance is 4 + 6 = 10 m.
Frequently asked questions
What should I show when a prompt says justify?
Give the relevant principle or evidence and connect it to the conclusion. For a direction or sign, state the convention that makes the direction or sign meaningful. Check the scoring guidelines for the specific released question.
Official sources and next reading
College Board AP Physics C: Mechanics exam information and released questions · AP calculator policy · 2027 AP exam schedule
Related AP exam vocabulary guide · eduKateSG vocabulary learning guide · Learn the Fencing Method