MYP Physics: The Physics of Everyday Electricity — FAQ

Electricity is hard because you can't see what you're measuring. Current, voltage and resistance are abstract quantities layered onto invisible charge flow, and everyday language — 'electricity flows out of the plug' — contradicts the actual model. That gap between casual talk and precise definitions is where most MYP 4-5 students drop marks in Criterion A.

Current (I, measured in amps) is the rate of charge flow past a point. Voltage, or potential difference (V, in volts), is the energy transferred per unit charge between two points. Resistance (R, in ohms) is how much a component opposes that flow. They're linked by Ohm's Law: V = IR.

Because the rules flip depending on the arrangement. In series circuits, current is the same everywhere but voltage splits across components. In parallel circuits, voltage is the same across each branch but current splits. Students memorise one rule and apply it to both — that's the exact mistake examiners see most.

Applying V = IR to the whole circuit using values from just one component, or forgetting to combine resistances first in a series or parallel network before substituting numbers. A close second: mixing units — using milliamps instead of amps — which throws the answer out by a factor of 1000.

Top marks in this unit come from linking calculation to explanation — Criterion A rewards you for stating the correct relationship (V = IR) and explaining why it applies, not just producing a number. Practise past-paper-style questions that ask you to 'explain' or 'justify', not just 'calculate'.

Build circuits by hand — physically or in a free circuit simulator — before you try to draw them from a textbook. Recognising a symbol on a page is different from predicting what happens when you add a second resistor. Then practise converting between a circuit diagram and a written description, in both directions.

Identify what you know (V, I or R), rearrange V = IR for the missing quantity, and check your units before substituting. For circuits with multiple resistors, find the total resistance first — sum them for series, use 1/R total = 1/R1 + 1/R2 for parallel — then apply Ohm's Law to the whole circuit.

Electricity is usually assessed under Criterion A (Knowing and understanding) for definitions and calculations, and Criterion B or C for the practical circuit-building investigations schools run alongside it. Some units also draw on Criterion D if students evaluate the societal impact of, say, household wiring safety or energy use.

Yes, if your school opts into the MYP eAssessment — but it's tested inside a combined Sciences paper, not a physics-only exam. According to the IB, the on-screen Sciences eAssessment has run since 2016 and, as of the 2025 assessment session, still mixes Biology, Chemistry and Physics questions in one two-hour paper.

State, describe, explain, calculate, analyse and distinguish are the ones I see most in electricity questions. 'State' wants a fact with no reasoning. 'Explain' wants a causal 'because' link. 'Calculate' demands full working, not just an answer — and MYP examiners routinely dock marks for a correct number with no method shown.

MYP electricity covers the foundations — current, voltage, resistance, series and parallel circuits, Ohm's Law — using single-step calculations. DP Physics builds directly on this with Kirchhoff's laws, internal resistance and EMF, and expects multi-step calculations with uncertainty analysis. A shaky grasp of MYP basics shows up fast in DP Physics topic 5 (Electricity and magnetism).

Not if they close the gap over the summer before DP starts. Electricity is one of the more forgiving topics to catch up on independently, because it's built on a small set of formulas rather than years of accumulated content. A focused few weeks on circuits and Ohm's Law usually gets a student back on level footing.

Look for three things: topic-specific revision notes that explain the current-voltage-resistance relationship clearly, a bank of practice questions with full worked solutions (not just final answers), and past-paper-style mock questions that use real MYP command terms. Circuit-building simulators are worth using too, since electricity is a genuinely hands-on topic.

Private one-to-one tutoring for MYP Physics typically runs anywhere from USD 30 to USD 80+ per hour depending on location and tutor experience, which adds up fast over a term. Self-study resources — revision notes, topical worksheets, question banks and mock papers — cost a fraction of that and let a student revise electricity at their own pace.