AP Physics 2 FRQ Guide 2026 — Free Response Tips, Scoring & Worked Examples
The AP Physics 2 free response section has 4 questions worth a combined 45 points. Unlike AP Physics 1, the Physics 2 FRQ emphasizes quantitative analysis, multi-part reasoning chains, and experimental design questions. This guide breaks down every question type, what graders look for, and how to avoid the most common errors.
Exam Format Overview
| Section | Content | Questions | Time | Weight |
|---|---|---|---|---|
| Section I | Multiple Choice | 50 questions | 90 min | 50% |
| Section II — FRQ 1 | Extended response (quantitative) | 1 question | ~25 min | ~25% |
| Section II — FRQ 2 | Short response | 1 question | ~10 min | ~10% |
| Section II — FRQ 3 | Short response | 1 question | ~10 min | ~10% |
| Section II — FRQ 4 | Lab/experimental question | 1 question | ~20 min | ~25% |
Total FRQ time: 90 minutes for all 4 questions. You have the AP equation sheet available for the entire FRQ section. The equation sheet does NOT contain all equations — you must know which equation applies to each situation.
FRQ Question Types
AP Physics 2 FRQs fall into four categories that appear consistently across exam years:
| Type | Description | Key Topics |
|---|---|---|
| Quantitative/Qualitative Translation | Given a physical scenario; calculate quantities AND explain conceptually | Circuits, fluids, optics, thermodynamics |
| Paragraph-Length Argument | Write a coherent paragraph explaining a physical phenomenon using physics principles | Any topic; tests conceptual understanding and communication |
| Lab/Experimental Design | Design or analyze an experiment: describe procedure, identify variables, predict results, explain sources of error | All units; requires IV, DV, controls, graphing |
| Graph/Diagram Analysis | Interpret or sketch a graph; label a diagram (ray diagram, circuit, field lines) | Optics (ray diagrams), E&M (field lines, circuits), modern physics (energy levels) |
How Physics 2 FRQs Are Scored
Each part of each FRQ is scored by awarding specific point-earning "response elements." AP Physics 2 graders are explicitly told to award points even for partially correct responses, as long as the partially correct part is correct on its own terms.
The Five Elements Graders Check
- Equation stated — Write the relevant equation from the formula sheet (or from memory) before substituting values
- Correct substitution — Substitute the given values with correct units
- Correct answer with units — Calculate the final numerical answer and include units
- Justification/explanation — Explain the physics reasoning behind your approach (why you chose that equation)
- Diagram requirements — Labels, direction arrows, and proportional representations where required
Paragraph-Length Argument Questions
These questions ask you to write a connected paragraph (not bullet points) explaining a physics phenomenon. Graders look for:
- A clear statement of the relevant physics principle (e.g., "By conservation of energy...")
- Correct application to the specific scenario
- A logical chain from principle → effect → conclusion
- Correct use of physics vocabulary (quantitative language preferred)
Diagrams and Equations
When to Draw a Diagram
Always draw a diagram when asked, but also draw one proactively for circuits, ray optics, and free-body-equivalent situations even when not explicitly required. A correct diagram can earn points independently of the calculation.
Ray Diagram Requirements
- Draw at least 2 rays from the object tip to locate the image
- Solid lines = real rays; dashed lines = virtual (extended behind mirror/lens)
- Always label: F (focal point), 2F (center of curvature), object, image
- Arrow on image must correctly show upright vs. inverted
- For virtual images (behind the mirror/lens), draw image as dashed
Circuit Diagrams
- Use standard symbols: — (resistor as rectangle or zigzag), ⟤⟥ (battery/EMF), — (wire), ≡ (capacitor)
- Label current direction with arrows (conventional current flows from + to −)
- For parallel circuits, explicitly show branching junctions
- Label all given values (R₁ = 10 Ω, etc.) on the diagram
Experimental Design Questions
Lab/experimental questions appear on virtually every AP Physics 2 exam. The question provides a scenario and asks you to design an experiment to test a hypothesis or determine a physical quantity.
What to Include in Every Lab Response
| Element | What to Write |
|---|---|
| Hypothesis / Goal | State what you're testing or measuring in one sentence |
| Materials | List specific equipment: rulers, force sensors, multimeters, light sources — not vague ("equipment") |
| Independent Variable (IV) | What you change: "voltage across the circuit" or "depth of the submerged object" |
| Dependent Variable (DV) | What you measure: "the current through resistor R₂" or "buoyant force measured by spring scale" |
| Controlled Variables | What you hold constant to make the test fair: temperature, fluid type, object shape |
| Procedure | Step-by-step description; mention taking multiple trials and averaging |
| Data analysis | What graph to plot (DV vs. IV), what the slope represents, how to extract the target quantity |
| Sources of error | Specific sources (parallax, friction, heat loss to environment) — not generic "human error" |
Worked Example — Fluid Statics
Problem: A wooden cube of side length 0.10 m and density 600 kg/m³ floats in water (ρ = 1000 kg/m³).
(a) What fraction of the cube is submerged?
(b) Calculate the buoyant force on the cube.
(c) Describe what would happen if the cube were placed in a fluid of density 500 kg/m³. Justify your answer using physics principles.
Part (a) solution:
For a floating object in equilibrium: Buoyant force = Weight of object
F_b = ρ_fluid × V_sub × g = ρ_object × V_total × g
ρ_fluid × V_sub = ρ_object × V_total
V_sub / V_total = ρ_object / ρ_fluid = 600/1000 = 0.60 (60% submerged)
Part (b) solution:
V_sub = 0.60 × (0.10)³ = 0.60 × 0.001 = 6.0 × 10⁻⁴ m³
F_b = ρ_water × V_sub × g = (1000)(6.0 × 10⁻⁴)(9.8) = 5.88 N ≈ 5.9 N
Part (c) solution (paragraph-style):
The cube would sink in a fluid of density 500 kg/m³. For an object to float, the fluid density must be greater than or equal to the object density. Since the cube's density (600 kg/m³) exceeds the fluid density (500 kg/m³), even when fully submerged the buoyant force (F_b = ρ_fluid × V_total × g = 500 × 0.001 × 9.8 = 4.9 N) would be less than the cube's weight (W = 600 × 0.001 × 9.8 = 5.88 N). Because the net force is downward, the cube sinks to the bottom of the container.
✓ States the principle (float condition) ✓ Calculates both forces ✓ Uses comparison to justify conclusion ✓ Written as a connected argument, not bullets
5 Most Common AP Physics 2 FRQ Mistakes
Many FRQ parts specify a required diagram. If asked to "draw a ray diagram to locate the image" and you skip it, you forfeit those points regardless of how correct your verbal description is. Always draw what's asked, with labels.
Writing C = ε₀A/d is correct, but then substituting the area of a circle instead of the stated plate area is a substitution error. Read each part carefully before substituting. The equation earns a point; the correct substitution earns another.
Units are checked on many numerical answer points. An answer of "5.88" earns less than "5.88 N." Always include units. When using SI units throughout, dimensional analysis can catch mistakes.
"Due to conservation of energy, the temperature increases" is penalized for vagueness. Specify which form of energy, which system, and exactly how energy is transferred. "Work done by the compression force on the gas increases the internal energy of the gas, raising its temperature" earns the point.
"Human error" is not an acceptable answer for a source of error. Identify specific, physics-based sources: "heat lost to the environment means less work is available for the piston" or "friction between the piston and cylinder walls reduces effective work output." Be specific.
Score Impact Table
| AP Score | Composite Range | Typical FRQ Performance |
|---|---|---|
| 5 | ~70–100 | Nearly complete responses on all 4 FRQs; correct diagrams; coherent paragraph arguments; specific error analysis |
| 4 | ~55–69 | Strong on quantitative questions; paragraph questions partially correct; lab design mostly complete |
| 3 | ~40–54 | Correct equations and set-up; calculation errors; diagrams present but improperly labeled |
| 2 | ~25–39 | Correct formulas stated; significant execution errors; paragraph questions too vague |
| 1 | 0–24 | Major conceptual gaps; wrong equations; diagrams missing or incorrect |
Related Resources
- AP Physics 2 Score Calculator
- AP Physics 2 Score Curve 2026
- AP Physics 2 Practice Test -- 30 Questions