AQA A level Physics required practicals

By The STEM-Tutor team · Updated October 2026

AQA A level Physics has twelve required practicals. You do them in class, and you are examined on them in the written papers. Here is the full list and how to revise them.

The twelve required practicals

1. Investigating how the frequency of a stationary wave on a string varies with length, tension or mass per unit length
2. Interference effects with a laser, such as Young's double slit or a diffraction grating
3. Determining g by a free-fall method
4. Determining the Young modulus of a wire
5. Determining the resistivity of a wire
6. Investigating the emf and internal resistance of a cell
7. Investigating simple harmonic motion with a mass-spring system or a pendulum
8. Investigating Boyle's law and Charles's law for a gas
9. Investigating the charge and discharge of a capacitor
10. Investigating how the force on a wire varies with magnetic flux density, current and length
11. Investigating magnetic flux linkage with a search coil
12. Investigating the inverse-square law for gamma radiation

Check the current AQA specification and practical handbook for the exact wording. Other boards have their own required or core practicals.

How practicals are examined

• Describing a method, including what to measure and how.
• Identifying variables and how to control them.
• Analysing data with graphs, gradients and intercepts.
• Calculating uncertainties and evaluating results.

How to revise them

1. For each practical, write the aim, the method in five steps, the graph you plot and what its gradient means.
2. Learn the main sources of uncertainty and how to reduce them.
3. Practise uncertainty calculations: percentage uncertainties add when quantities are multiplied or divided.
4. Do past exam questions on practical skills from your board.

The practical endorsement

In England, A level Physics also has a separately reported practical endorsement, assessed by your teacher during the course. It does not change your grade, but many universities expect a pass.

The skills behind every practical

Examiners care less about remembering one particular method and more about the skills that every practical shares. You should be able to identify independent, dependent and control variables, choose suitable instruments and explain their resolution, take repeat readings, plot a straight-line graph, and work out uncertainties. If you understand these skills, you can answer questions on practicals you have never seen before.

Uncertainties, step by step

The absolute uncertainty is the range a value could lie in, such as ±0.5 mm. The percentage uncertainty is the absolute uncertainty divided by the value, times 100. When you multiply or divide quantities, add their percentage uncertainties. When you raise a quantity to a power, multiply its percentage uncertainty by that power. When you add or subtract quantities, add their absolute uncertainties.

Example 1: combining uncertainties

A wire's diameter is 0.50 ± 0.01 mm and its length is 1.000 ± 0.002 m. Find the percentage uncertainty in its resistivity, given that the resistance has 2% uncertainty.

• Diameter: 0.01/0.50 = 2%. Area depends on d², so 4%.
• Length: 0.2%. Resistivity = RA/L, so the total is 2 + 4 + 0.2 = 6.2%.
• The diameter dominates, which is why you measure it with a micrometer at several points along the wire.

Example 2: g by free fall

A ball falls from rest. A graph of h against t² has a gradient of 4.85 m/s². Find g.

• h = ½gt², so the gradient is g/2.
• g = 2 × 4.85 = 9.7 m/s².

Example 3: the Young modulus

A wire 2.0 m long with area 2.0 × 10⁻⁷ m² stretches 1.0 mm under a 20 N load. Find the Young modulus.

• Stress = 20/2.0 × 10⁻⁷ = 1.0 × 10⁸ Pa. Strain = 1.0 × 10⁻³/2.0 = 5.0 × 10⁻⁴.
• E = stress/strain = 2.0 × 10¹¹ Pa.

Example 4: emf and internal resistance from a graph

A graph of terminal pd V against current I is a straight line with intercept 1.52 V and gradient −0.80 V/A. Find the emf and internal resistance.

• V = ε − Ir, so the intercept is the emf and the gradient is −r.
• ε = 1.52 V and r = 0.80 Ω.

Example 5: capacitor discharge

A capacitor discharges through a resistor. A graph of ln V against t has gradient −0.050 s⁻¹. Find the time constant.

• V = V₀e^−t/RC, so ln V = ln V₀ − t/RC.
• Gradient = −1/RC, so RC = 20 s.

Turning equations into straight lines

Many practical questions ask what to plot to get a straight line. Compare the equation with y = mx + c. For a pendulum, T = 2π√(L/g), so plot T² against L and the gradient is 4π²/g. For exponential decay, take natural logs and plot ln V against t. For an inverse square law, plot intensity against 1/d². Being fluent at this saves a lot of time in the exam.

Common mistakes

• Confusing accuracy (close to the true value) with precision (repeat readings close together).
• Drawing a line of best fit that is forced through the origin when the data does not justify it.
• Plotting graphs that use less than half the grid.
• Forgetting safety points, such as using goggles with stretched wires or keeping distance from radioactive sources.

Practice questions

Try each one before opening the answer.

Frequently asked questions

Do the practicals appear in the written exam?

Yes. A good share of marks test practical skills, often through the required practicals, so revise them as carefully as the theory.

Is the practical endorsement part of my grade?

No. It is reported separately as a pass or not classified, but universities may ask for it.

Key takeaways

• Learn the shared skills, not just the methods.
• Multiply or divide: add percentage uncertainties.
• Powers multiply the percentage uncertainty.
• Rearrange equations into y = mx + c to choose what to plot.
• Know the gradient and intercept meaning for each practical graph.

Where to go next

Practicals connect to every topic in the course.

• A level Physics electricity
• A level Physics waves
• A level Physics revision

How to revise the practicals

For each practical, make one revision card with five headings: aim, apparatus, method, graph, and sources of error. Under graph, write what you plot, what the gradient means and what the intercept means. Under sources of error, note the biggest uncertainty and how to reduce it. Then test yourself by covering the card and explaining the practical out loud, as if to a friend. Finally, practise past-paper questions that describe an unfamiliar experiment, because these test whether you can apply the skills rather than repeat a method.

Treat each practical as a story: what you changed, what you measured, what the graph showed, and how you could make it better.