How to Remember IGCSE Physics Equations

Equations are the tools of physics problem solving. Knowing them instantly, without hesitation, frees your working memory to focus on the problem.

Strategy 1: Group by topic

Organise equations by the topic they belong to. This creates associations that help recall.

Motion: $v = d/t$, $a = \Delta v / t$, $F = ma$, $W = mg$, $p = mv$

Energy: $E_k = \frac{1}{2}mv^2$, $\Delta E_p = mg\Delta h$, $W = Fd$, $P = E/t$, efficiency $=$ useful out / total in

Waves: $v = f\lambda$, $n = \sin i / \sin r$

Electricity: $V = IR$, $P = IV$, $Q = It$, $E = VIt$, $V_p/V_s = N_p/N_s$

Thermal: $E = mc\Delta\theta$, $E = mL$, $pV =$ constant, $p/T =$ constant

Pressure: $p = F/A$, $p = \rho gh$

Strategy 2: Flashcards with worked examples

Front: the quantity name and a sample question. Back: the equation and a brief worked solution.

Test yourself daily. Remove cards you know well; focus on the ones you forget.

Strategy 3: Daily equation drills

Each morning, write all equations from memory. Time yourself. Mark the ones you missed. Practise those specifically.

Target: under 3 minutes for all equations with no errors.

Strategy 4: Use equations in context

Solving real questions cements the equation in memory far better than reading a list. After learning an equation, immediately practise 3 to 5 questions that use it.

Common errors and how to correct them

1. Confusing similar equations ($P = IV$ vs $P = E/t$; both are power but used in different contexts).
2. Not knowing which equation to use because you never practised selecting from the full set.
3. Memorising equations without understanding the symbols and units.

How to apply this in an exam

If you go blank on an equation, work from the units. Power is in watts (J/s), so $P = E/t$. This unit-based reasoning can recover an equation when memory fails.