AP Physics 1 units and review checklist

By Ashraf Bhura, Co-Founder, STEM-Tutor · Updated October 2026

AP Physics 1 is organised into eight units of algebra-based mechanics. Here is what each one covers and what to review before the exam.

The eight units

1. Kinematics: position, velocity and acceleration in one and two dimensions, including projectiles and motion graphs.
2. Force and Translational Dynamics: Newton's laws, free-body diagrams, friction, springs, circular motion and gravitation.
3. Work, Energy, and Power: kinetic and potential energy, work, conservation of energy and power.
4. Linear Momentum: impulse, conservation of momentum and collisions.
5. Torque and Rotational Dynamics: torque, rotational inertia and rotational versions of Newton's laws.
6. Energy and Momentum of Rotating Systems: rotational kinetic energy, angular momentum and rolling.
7. Oscillations: simple harmonic motion of springs and pendulums.
8. Fluids: density, pressure, buoyancy and fluid flow.

Check the current course and exam description on AP Central for unit weightings and exam timings.

Review checklist

• Can you sketch position, velocity and acceleration graphs for the same motion and move between them?
• Can you draw a correct free-body diagram for any object, including on slopes and in circles?
• Can you decide quickly whether forces, energy or momentum is the best approach?
• Can you explain why momentum is conserved in a collision but kinetic energy may not be?
• Can you treat rotation the same way as linear motion: torque like force, rotational inertia like mass?
• Can you explain what changes the period of a spring or a pendulum, and what does not?
• Can you explain buoyancy using pressure differences, not just a formula?

Where students lose the most marks

• Mixing up velocity and acceleration directions.
• Missing a force, or adding a "force of motion" that does not exist.
• Using conservation of energy when friction does work.
• Writing a calculation where the question asks for a written justification.

How to review in the last month

1. Take one timed section each week and mark it honestly.
2. Spend most of your time on the two weakest units from those sections.
3. Practise writing short, clear explanations for free-response questions.

Example questions, one per unit

These short examples show the kind of thinking each unit expects.

• Kinematics: a car accelerates from rest at 2 m/s² for 5 s. Distance = ½ × 2 × 25 = 25 m.
• Forces: a 4 kg box is pulled with 20 N against 8 N of friction. Acceleration = 12/4 = 3 m/s².
• Energy: a 0.5 kg ball dropped from 3.2 m reaches v = √(2 × 9.8 × 3.2) ≈ 7.9 m/s.
• Momentum: a 1 kg cart at 4 m/s hits a 1 kg cart at rest and they stick: v = 2 m/s.
• Torque: a 30 N force at 0.5 m from a hinge, at 90°, gives τ = 15 N·m.
• Rotational energy: a disc with I = 0.2 kg·m² spinning at 10 rad/s stores ½ × 0.2 × 100 = 10 J.
• Oscillations: a 1 m pendulum has T = 2π√(1/9.8) ≈ 2.0 s.
• Fluids: pressure 2 m below the surface of water is 1000 × 9.8 × 2 = 19,600 Pa above atmospheric.

How the units connect

The units are not separate boxes. The same three tools solve most problems:

• Forces (Newton's laws) when you need acceleration or time.
• Energy when you need speed after a change in height or distance.
• Momentum when objects collide or push apart.

Rotation repeats all three in a rotational form, and oscillations and fluids apply them to new situations. That is why choosing the right tool is the most important skill in the course.

A weekly review routine

1. Monday: rewrite the key ideas of one unit on a single page, from memory.
2. Wednesday: ten mixed multiple-choice questions across all units so far.
3. Friday: one free-response question, marked with the official scoring guidelines.
4. Weekend: redo every question you got wrong that week.

Frequently asked questions

Which AP Physics 1 unit is the hardest?

Most students find rotation (Units 5 and 6) the hardest, because it adds new quantities. Treat it as linear motion with new names and it becomes much more manageable. See our rotation guide.

How much maths do I need?

Algebra and basic trigonometry: rearranging equations, sine and cosine for components, and reading graphs. No calculus is needed.

Should I memorise equations?

No. You get an equation sheet. Spend the time on understanding when each equation applies. See our equation sheet guide.

Practice questions

Try each one before opening the answer.

Building a one-page summary for each unit

A single page per unit is one of the most effective review tools. For each unit, include the key definitions, the main equations with what each symbol means, one labelled diagram, and the two mistakes you make most often. Rewriting these from memory every few weeks keeps the whole course fresh before the exam.

One more worked example

Combining units: energy and momentum

A 2 kg block slides from rest down a 0.8 m high frictionless ramp and hits a 2 kg block at rest; they stick. Find their speed.

• Energy on the ramp: v = √(2 × 9.8 × 0.8) ≈ 3.96 m/s.
• Momentum in the collision: 2 × 3.96 = 4v, so v ≈ 1.98 m/s.
• Each stage needs a different unit's tool. Recognising the stages is the key skill.

Extra practice

Try each one before opening the answer.

More questions students ask

How long should I spend reviewing?

Steady weekly practice through the year, with extra timed practice in the final two months, works better than a last-minute cram.

Are the units examined equally?

No. Check the current unit weightings in the course and exam description on AP Central.

Key takeaways

• AP Physics 1 has eight units of algebra-based mechanics, including fluids.
• Forces, energy and momentum solve most problems.
• Rotation mirrors linear motion with new quantities.
• Review with one-page summaries and mixed practice.
• Check unit weightings in the current course description.

Quick check