Inside the on-screen Physics exam: tasks, tools, timing and command terms
By the end of this lesson you will be able to
- Describe the structure of the MYP Physics on-screen examination: 100 marks, 120 minutes, about 25 marks for each of Criteria A, B, C and D.
- Identify each on-screen tool and item type, and state the mistake that loses marks with each one.
- Plan your 120 minutes so that the design question and the long discuss-and-evaluate question get the time their marks deserve.
- Distinguish between the command terms used in Physics papers — state, outline, describe, explain, suggest, calculate, determine, justify, compare, evaluate, discuss — and answer at the depth each demands.
- Interpret markscheme conventions (ECF, WTTE, ORA, “unit awarded independently”, “do not accept”) and use them to mark your own work honestly.
You met this before
- MYP sciences are assessed on four criteria: A Knowing and understanding, B Inquiring and designing, C Processing and evaluating, D Reflecting on the impacts of science, each judged on levels 0–8.
- SI base units: metre (m), kilogram (kg), second (s), ampere (A), kelvin (K). Convert to base units before you substitute.
- Prefixes: k (kilo) is 10³; M (mega) is 10⁶; m (milli) is 10⁻³; μ (micro) is 10⁻⁶; n (nano) is 10⁻⁹.
- The independent variable is what you change; the dependent variable is what you read from an instrument; each control variable is kept at a stated value.
- A mean is the sum of the trials divided by their number, rounded to the precision of the raw readings.
- Every unit exam in this course (Units 1–10) used the same shape as the real paper: Task 1 Criterion A, Task 2 Criteria B and C, Task 3 Criterion D.
A trolley travels 1.20 m in 450 ms. Calculate its average speed in m s⁻¹, and state which quantity had to be converted first.
Reveal
450 ms = 0.450 s
v = d ÷ t
v = 1.20 m ÷ 0.450 s
v = 2.67 m s⁻¹ (3 significant figures, like the data)
The time had to be converted from milliseconds to seconds. The Physics May 2025 report named exactly this: “the time in milliseconds was commonly not converted to seconds”.
Revise it in full: Year 1 · Being a scientist · Lesson 2 — Measuring: how do you know your number is right? · Year 1 · Being a scientist · Lesson 4 — Tables and graphs: making the pattern visible · Year 3 · Physics · Mechanics and space exploration · Lesson 1 — Describing motion
The puzzle
Two students sit the same Physics paper. On a quiz of definitions and equations they score the same.
One scores 76. The other scores 58. In May 2025 that was the gap between a grade 7 and a grade 5.
Neither knows more physics than the other. So where did 18 marks go?
The Physics reports answer this every session. Marks go on units left off, milliseconds not converted, “proportional” claimed for a curve, a table with units in every cell, and a discussion that stops without a conclusion. None of that is new physics. All of it is fixable.
Before reading on, predict three ways a student who knows the physics could still lose marks on the on-screen exam. Write them down, then compare.
Compare your answer
The reports list the same losses every session. A missing or wrong unit — the unit mark is often awarded separately, so “11.1” without “kW” drops a mark. A prefix not converted (nm, ms, km, days). Precision not matched: “20 instead of 20.0” (May 2025).
A command term ignored: a description where “explain” wanted a mechanism. A concluding appraisal missing: “a possible 2 marks” lost (May 2025). None of these is a gap in physics.
The science of the exam — structured notes
1.1 The paper at a glance: 100 marks, 120 minutes, four criteria
The MYP Physics eAssessment is one on-screen examination of 2 hours and 100 marks. It assesses all four criteria, each worth about a quarter of the marks: A Knowing and understanding, B Inquiring and designing, C Processing and evaluating, D Reflecting on the impacts of science.
In this course we practise it as three tasks — Task 1 (A, 25 marks), Task 2 (one investigation, B 25 + C 25) and Task 3 (a real-world issue, D 25). The real paper mixes a little more: one numbered question may carry A and C marks, and a data question may sit next to a design question.
The shape is stable. The five Physics papers from 2021 to 2023 each have eight questions. They open with short knowledge items, put one long design question in the middle, and end with a long discuss and evaluate question.
| Session | Questions | The design question | The longest discuss-and-evaluate question |
|---|---|---|---|
| May 2021 | 8 | Q5b, surface area of a parachute and time to fall [13] | Q8, drones in surveillance [14] |
| November 2021 | 8 | Q6b, number of bulbs in series and current [15] | Q8b, Malta’s energy options [12] |
| November 2022 | 8 | Q5, voltage and the time for a motor to lift a mass [14] | Q8b, ultrasound and X-ray imaging [16] |
| May 2023 | 8 | Q5b, temperature and the circumference of a balloon [14] | Q7d, mobile-phone location tracking [13] |
| November 2023 | 8 | Q6a, sponge thickness and table-tennis ball bounce [14] | Q8, upgrading houses to passive standards [13] |
Two things follow. First, 27–30 marks of every paper sit in just two questions — the design and the long discussion. Second, those long questions come with bullet points, and the markscheme follows the bullets. The other six questions are mostly data and knowledge items of 7–20 marks, each built round one context: Marconi’s radio, horses on a hill, Galileo’s ramp, a kidney stone.
“Every question on the real Physics paper tests only one criterion, so the paper has exactly three sections.”
Reveal answer
False. The questions are numbered continuously, one to eight, and the criteria are spread across them. November 2022 Q6, for example, mixed a knowledge calculation (the gain in gravitational potential energy) with organising raw data into a table (Criterion C).
What is stable is the pattern: short knowledge items first, investigations in the middle, discussion last.
1.2 The on-screen tools and item types: what each asks of you
Every item is answered on screen. The toolbar gives you a calculator, a formula sheet, a symbol palette and, where an item needs them, a table tool, a graph plotter, a drawing canvas and a measuring tool. Simulations and videos are the stimulus for many items.
Each item type has its own way of losing marks. The table lists the types in the Physics and Integrated Sciences papers from 2021 to 2023, with a real item and the trap.
| Item type and tool | What you do | Real item | The trap |
|---|---|---|---|
| Select (options or drop-down) | Click one option, or pick words inside a sentence | May 2021 Q1b: the bending of radio waves round obstacles — diffraction | Choosing the near-miss (refraction); leaving a drop-down on “?” |
| Drag-and-drop labels | Drag words or particles into boxes on a diagram or equation | May 2023 Q3d: ⁴₂α and ⁰₋₁β into two decay equations | Not checking that mass and atomic numbers balance on both sides |
| Numeric box with the calculator | Type a value; working can go in the box | May 2023 Q1e: minimum power of a horse, in kW [3] | Answer in W when kW was asked; no working, so no ECF |
| Table tool (“Organize”) | Build a results table from a notebook of raw data | November 2021 Q4a: voltage and current for component X [6] | Units in every cell; rows not in order; decimals inconsistent; mA not converted |
| Graph plotter | Set scales, drag points, draw a line of best fit | May 2021 Integrated Sciences Q4d: current against voltage [5] | Uneven scale; points using less than half the grid; line forced through an anomaly |
| Drawing canvas | Drag circuit symbols and wires into place | November 2022 Q4d: ammeter in series, voltmeter across the motor [3] | Voltmeter in series; extra components added |
| Measuring tool or simulation | Move a screen, ruler or slider and read a scale | May 2021 Q6a: image distance from a sharp image on a lens bench [3] | Reading the scale position instead of the distance from the lens |
| Open response box | Type the answer; long questions show bullets above a large box | November 2022 Q8b: ultrasound and X-rays [16] | A bullet ignored; no concluding appraisal |
The formula sheet matters more in Physics than in any other science paper. Items say “use the formula sheet” (May 2023 Q1e, Q2d, Q4d; November 2023 Q3c), so you do not need to memorise every equation. You do need to recognise which one fits, rearrange it and convert units first. The sheet will not tell you that 750 nm is 7.50 × 10⁻⁷ m.
The Physics May 2023 report praised the “increased number of students using the online tools to present their working”. Working typed into the box is what lets an examiner award method marks and ECF.
A ball rolls from rest down a ramp. The table has columns distance / m, time / s and (time)² / ______. The rows above show 1.04, 1.93, 3.06 and 3.92. For the last row the time is 2.19 s. Label the missing unit and calculate the missing value.
(time)² = t × t
(time)² = 2.19 s × 2.19 s
(time)² = 4.7961 s²
(time)² = 4.80 s² (2 decimal places, matching the column)
The markscheme gave one mark for the unit s² (with a real superscript), one for the calculation and one for 4.80 to two decimal places. Typing 4.7961 showed the arithmetic but not the judgement.
A current column reads 0.20, 0.41, 0.60, 0.81 and 1.01 A. The notebook gives the current at 3.0 V as 601 mA. What value do you type into the table?
Reveal answer
601 mA = 601 ÷ 1000 A
601 mA = 0.601 A
Typed value: 0.60 (2 decimal places, like the rest of the column; unit in the heading only)
This is November 2021 Q4a: the markscheme gave marks for units in the headers only, for data in order and for every current to 2 d.p.
A candle is fixed at the 0 cm mark of a metre rule and a convex lens at the 30.0 cm mark. You slide the screen until the image is sharp. The magnifier on the screen shows the scale reading 42.8 cm. Determine the image distance di, the distance from the lens to the screen.
di = screen reading − lens reading
di = 42.8 cm − 30.0 cm
di = 12.8 cm
The markscheme awarded the reading (42.8 ± 0.1), the subtraction (with ECF) and the unit cm, which was “awarded independently if seen anywhere”. The trap is typing the reading, 42.8, as if it were the distance.
A student builds a table with the table tool. Headings: “Voltage” and “Current”. Cells: 1.0 V, 2.0 V, 4.0 V, 3.0 V, 5.0 V in the first column; 0.2 A, 0.41 A, 0.81 A, 601 mA, 1.01 A in the second. Find four errors.
Reveal answer
Units are in every cell instead of in the headings only: write “Voltage / V” and “Current / A”. The rows are not in order: 4.0 V comes before 3.0 V.
The decimals are inconsistent: 0.2 should be 0.20. And 601 mA has not been converted: it is 0.60 A. These are the four marking points of November 2021 Q4a; the November 2025 report says table questions cause problems “as it always seems to”.
The corrected table:
| Voltage / V | Current / A |
|---|---|
| 1.0 | 0.20 |
| 2.0 | 0.41 |
| 3.0 | 0.60 |
| 4.0 | 0.81 |
| 5.0 | 1.01 |
1.3 Timing: 120 minutes, 100 marks, and where the minutes go
The simplest rule is about 1.2 minutes per mark. A 2-mark item deserves under three minutes; a 14-mark design deserves about 17 minutes; a 16-mark discussion about 19. Applied to the course’s three-task shape, it gives this plan.
| Block | Marks | Minutes | What you are doing |
|---|---|---|---|
| First read | — | 5 | Scroll the whole paper; find the design question and the long discussion; note their marks |
| Task 1 — Criterion A | 25 | 25 | Short items; formula sheet open; never more than 3 minutes on a 1–2 mark item |
| Task 2 — Criteria B and C | 50 | 55 | Design (about 17 minutes), then tables, graphs and gradients |
| Task 3 — Criterion D | 25 | 30 | Sources first (5 minutes), then the long answer bullet by bullet |
| Check | — | 5 | Blanks, units, superscripts, precision, the concluding appraisal |
Physics students have usually found the time fair. The Physics May 2026 report noted “very few blank responses”. The risk is not running out of paper — it is spending twelve minutes on a 3-mark calculation you cannot crack. Write what you have, show your working for method marks, note the question number and move on.
At 75 minutes a student has finished everything up to the design question. Remaining: the design [14], a data question [10] and a discuss-and-evaluate question [13]. How should the last 45 minutes be split?
Reveal answer
37 marks remain in 45 minutes, about 1.2 minutes per mark: design about 16 minutes, data about 12, discussion about 15, leaving 2 minutes to check.
Long questions are marked point by point against their bullets, so a structured partial answer to each scores far more than a perfect answer to one and nothing on another. The concluding appraisal alone is often worth 2 marks, so write it even if the middle of the discussion is thinner than you wanted.
1.4 Command terms: the verb decides the depth
Every question starts with a command term. It tells you how deep the marks go. The Physics May 2025 report flagged “the use of the command term ‘evaluate’ in addition to ‘discuss'” for extended questions. Every Biology report since 2023 has made the same point about command terms in general.
| Command term | What it demands | From a real Physics paper |
|---|---|---|
| Select / Identify | Pick or name the one right thing from what is given | May 2021 Q1b: the phenomenon in the animation — diffraction |
| State | A name, value or short fact; no explanation | November 2023 Q1b: an object in the Solar System not made by humans — a comet |
| Label | Place names or values on a diagram | November 2023 Q3a: light, 5 J and thermal, 95 J on a Sankey diagram |
| Outline | A brief account: two linked points for two marks | May 2021 Q3f: why reducing car fuel is globally significant — CO₂, then climate change |
| Describe | What happens, or what the data show, in detail | May 2023 Q4e: as pressure increases volume decreases, inversely |
| Explain | Reasons: a chain from cause to effect through the mechanism | May 2023 Q2b: why red light is at the top of the spectrum [3] |
| Suggest | A plausible idea in an unfamiliar context | May 2021 Q4f: why a water clock made sharing results hard |
| Calculate | A numerical answer with working and unit | May 2023 Q1e: minimum power of horse B, in kW [3] |
| Determine | Obtain one value, often from a graph | November 2022 Q1c: the half-life of barium-141, 18.5 min |
| Formulate | A testable hypothesis or research question | May 2021 Q5a: If … then … because, with forces and particle theory [3] |
| Justify | Valid reasons or evidence for a choice | November 2022 Q2e: which student is right about evaporation |
| Compare (and contrast) | Similarities and differences, each in a sentence naming both | November 2022 Q2b: evaporation and boiling [2] |
| Organize / Present | Build a correct table from raw data | November 2023 Q5c: coefficient of restitution table [6] |
| Construct / Draw | A circuit, line of best fit or diagram with standard symbols | November 2021 Q6a: two bulbs and an ammeter in series [3] |
| Design | A plan: variables, hypothesis, equipment, method, sufficient data, safety | November 2021 Q6b [15] |
| Evaluate / Discuss | Evaluate: weigh strengths and limitations. Discuss: arguments on both sides. Both end in a supported judgement | November 2023 Q4h: evaluate a prediction [3]; November 2022 Q8b [16] |
One question says “Outline how passive houses stay warm while needing less heat” [2]. Another says “Use kinetic theory to explain why the balloon expands when the gas is heated” [3]. Write a one-line plan for each.
Reveal answer
Outline [2]: good insulation reduces heat loss [1], so less extra heat is needed to keep the inside at a comfortable temperature (November 2023 Q7a) [1].
Explain [3]: the particles gain kinetic energy and move faster [1] → they hit the walls more often and with more force [1] → the pressure rises, so the elastic wall is pushed out and the balloon expands [1] (November 2021 Q1c). Three marks means three linked steps, reaching the particles.
“Compare the efficiency of an LED with that of a filament bulb” [3]. The filament bulb gives 5 J of light per 100 J in; the LED gives 0.02 W of light from 0.05 W in. Write the answer.
Reveal answer
Filament efficiency = 5 J ÷ 100 J × 100
Filament efficiency = 5 % [1]
LED efficiency = 0.02 W ÷ 0.05 W × 100
LED efficiency = 40 % [1]
So the LED is eight times as efficient as the filament bulb (40 % compared with 5 %) [1]. The November 2023 Q3d markscheme gave the comparison mark only when both efficiencies had been found.
1.5 Reading the stem, the bullets and the stimulus
Before you type anything, find four things. The command term. The marks — each mark is usually one point. The object — “the height of the first bounce”, not “the ball”. Any constraint: “give your answer in kW”, “to two significant figures”, “in scientific notation”, “include a unit”, “use the formula sheet”, “refer to particle theory”.
In Physics the constraints carry marks of their own. May 2021 Q1c gave a separate mark for writing the time in standard form; May 2023 Q7a gave separate marks for two significant figures and for the unit hertz. Underline them as you read.
Long questions add bullets; the markscheme follows them. Stimulus — a video transcript, a simulation, a table — is your raw material, not your answer: “This was information that was given in the question and as such was not worthy of credit” (Physics May 2024).
| Stem phrase | What it forces |
|---|---|
| “Give your answer to 2 significant figures” | Exactly two: 7.3, not 7.27 or 7 |
| “In scientific notation” | a × 10ⁿ with 1 ≤ a < 10: 2 × 10⁻⁵ s, not 0.00002 s |
| “Include a unit” | A mark that is often awarded independently of the number |
| “Refer to particle theory / forces / energy” | The mechanism: collisions, resultant force, named energy stores |
| “Use your answer to part (e)” | ECF: your earlier value, even if wrong, can carry the method mark |
| “From the perspective of a country” | Argue from that seat only (May 2023: an individual’s view scored nothing) |
“Calculate the time taken for the radio message to travel 6 km. The speed of radio waves is 3.0 × 10⁸ m s⁻¹. Give your answer in scientific notation.” A student types: “t = 6 ÷ 300 000 000 = 0.00000002”. What is wrong?
Reveal answer
The distance was not converted: 6 km is 6000 m. The answer is not in scientific notation, and there is no unit.
t = d ÷ v
t = 6000 m ÷ (3.0 × 10⁸ m s⁻¹)
t = 2 × 10⁻⁵ s
May 2021 Q1c gave a mark for the conversion, one for the value and one for standard form — which was “awarded even if the value is wrong but written in standard form”.
1.6 How the markscheme thinks: ECF, WTTE, ORA and independent marks
ECF — “error carried forward”: a later step that uses your wrong earlier value correctly still earns its marks. WTTE — “words to that effect”. ORA — “or reverse argument”: the same idea argued the other way round.
Independent marks are common in Physics: the unit, the significant figures and the standard form are often separate marks, so a correct unit on a wrong number still scores. Correct answer alone: many calculations say “award all marks for the correct final answer” — but only if it is right, so show working anyway.
Gated marks need an earlier mark first: in May 2023 Q6e, “the hypothesis is not valid” scored only after the trend and the proportionality points. Do not accept lists near-misses: “unnamed greenhouse gases” for CO₂ (May 2021 Q3f); “deformation of the ball” as the energy lost (November 2023 Q4d).
“If my number is wrong, writing the unit is pointless.”
Reveal answer
False. The unit mark is frequently awarded independently. May 2023 Q7a gave one mark for the frequency range, one for two significant figures and a separate mark for Hz or s⁻¹. In May 2026 Q1b, the report notes that students without a unit “got only 1 mark out of the 2”.
A horse of weight 5100 N climbs a hill 12 m high in 5.50 s. A student calculates the work done as 5100 × 1.2 = 6120 J (a slip with the height), then the power as 6120 ÷ 5.50 = 1112.7 W, and writes “1.11 kW”. The markscheme gives 1 mark for work, 1 for power and 1 for the answer in kW, with ECF. How many marks, and what is the correct answer?
Reveal answer
The work mark is lost. With ECF the power and the kW conversion are marked on 6120 J, and both are correct for that value, so 2 of 3.
W = F × d
W = 5100 N × 12 m
W = 61 200 J
P = W ÷ t
P = 61 200 J ÷ 5.50 s
P = 11 127 W
P = 11.1 kW (3 significant figures)
This is May 2023 Q1e, where “ECF applies” was written into the markscheme.
Try it — work the lab as an on-screen data question
The pendulum lab practises the Criterion C skills the Physics May 2026 report named: “demonstrating direct proportionality, linearising data, determining appropriate gradient units and interpreting the physical meaning of gradients”. A bob hangs on a string of length L; you time ten swings with a stopwatch.
A student’s mean times for 10 swings are 8.97 s (0.20 m), 12.69 s (0.40 m), 15.54 s (0.60 m), 17.94 s (0.80 m) and 20.06 s (1.00 m). Calculate T² for 0.40 m and 1.00 m, the gradient, and g [4].
Reveal answer
T(0.40 m) = 12.69 s ÷ 10 = 1.269 s
T² = 1.269² = 1.610 s²
T(1.00 m) = 20.06 s ÷ 10 = 2.006 s
T² = 2.006² = 4.024 s² [1]
gradient = (4.024 − 1.610) s² ÷ (1.00 − 0.40) m
gradient = 2.414 s² ÷ 0.60 m
gradient = 4.02 s² m⁻¹ [1 value, 1 unit]
g = 4π² ÷ 4.02 s² m⁻¹
g = 9.82 m s⁻² [1]
Common mistakes to avoid
- Leaving units off, or typing them with letters — “m/s^2” instead of m s⁻², “C°” instead of °C; the unit is often a separate mark.
- Substituting before converting — ms, km, nm, MJ and days go to base units first.
- Ignoring the stated precision — “20 instead of 20.0” (Physics May 2025) and “to 2 significant figures” lose marks on correct physics.
- Treating the paper as evenly timed — the design and the long discussion hold 27–30 marks; protect their minutes.
- Answering the topic, not the command term — a description where “explain” asked for the mechanism.
- Copying the stimulus back — “not worthy of credit” (Physics May 2024).
- Hiding the working — without it there is no ECF and no method mark.
- Tables with units in every cell or rows out of order — the Organize item’s four easy marks.
Study smart: how this is examined
Study routine. Today: copy the command-term table from memory, then check it. In two days: take five calculation questions from your Unit 1–10 exams and, for each, write only the conversions, the equation and the precision required.
In a week: sit one Physics past-paper question in the practice course with a timer set at 1.2 minutes per mark, and note every item where you lost a unit or a significant figure.
How we found out — why physics agrees on units
In May 2021 the Physics paper asked why Galileo’s water clock made it hard to share his results. The answer — nobody else had an identical clock — is the reason the International System of Units exists. For most of history every town had its own foot, its own pound and its own hour.
In the 1790s revolutionary France defined the metre as one ten-millionth of the distance from the North Pole to the Equator through Paris, and surveyors Jean-Baptiste Delambre and Pierre Méchain spent seven years measuring it. In 1875 seventeen nations signed the Metre Convention, and in 1889 platinum–iridium prototypes of the metre and kilogram were kept near Paris.
In 1960 the system was named the Système international d’unités — SI. The last physical artefact went on 20 May 2019, when the kilogram was redefined by fixing the value of the Planck constant. Every SI unit is now defined by constants of nature that any laboratory can reach.
That is why the markscheme insists on the unit. A number without one cannot be checked, compared or used — exactly Galileo’s problem with his water clock.
Explain why defining the kilogram by a constant of nature is better than defining it by one metal cylinder kept in a vault.
Reveal answer
A single object can change — gain dirt, lose atoms when cleaned — and comparisons with it drifted by tens of micrograms over a century. It can only be reached by visiting it.
A constant of nature is the same everywhere and for ever, so any well-equipped laboratory can realise the kilogram independently and results agree without anyone travelling to Paris.
Where it is used now
- Engineering drawings. Engineers building a solar farm in Botswana or a bridge anywhere in the world write every quantity with a unit and a tolerance; a missing unit is a rejected drawing.
- Medicine. Radiotherapy doses are given in grays and infusion rates in mL h⁻¹; a prefix error of 1000 is the kind of mistake hospitals build double-checks against.
- Aviation. In 1983 an Air Canada jet ran out of fuel in flight after a fuel load was calculated in pounds instead of kilograms; the crew glided it to a safe landing at Gimli, Manitoba.
- Digital testing. Driving-theory tests, university entrance tests and professional licences are increasingly on screen, with the same select, drag-and-drop and typed-response items.
Science now — and the scientist you need to be
What is happening in 2026
MYP eAssessment has been on screen since its first examinations in May 2016. The Physics paper is now a mature format: simulations with sliders, video with transcripts, a formula sheet, a graph plotter and a drawing canvas for circuits.
The IB is revising the MYP (“Enhancing the MYP”), with the first new-style eAssessment expected in May 2030; the physics and the skills you are practising carry forward.
Around you, physics has moved on screen too. Data are logged by sensors, fitted in spreadsheets and plotted by software; AI assistants can explain a topic, quiz you and check a calculation. Recall is cheap. What the Physics reports keep asking for is judgement — the right equation, the right units, the right precision and a conclusion that weighs the evidence.
The mindshift
What you need to be able to do
Read any question for its command term, marks, object and constraint; plan 120 minutes; convert and type values with the right precision and symbols; and mark your own work with the markscheme’s conventions.
See an example
For Unit 4 Thermal physics an assistant wrote “Explain why a pan handle is made of plastic [3]”. Its model answer — “plastic is an insulator” — is a statement worth one mark.
A full answer adds the mechanism: plastic has no free electrons and its molecules pass on vibrations slowly, so it is a poor conductor [1]; little thermal energy is conducted from the hot base to the hand [1]; so the handle stays cool enough to hold without a burn [1].
Key terms
| eAssessment | The MYP on-screen examination: 2 hours, 100 marks, Criteria A–D. |
| Command term | The verb at the start of a question that sets the depth and type of answer. |
| Formula sheet | The on-screen list of equations; you choose, rearrange and apply the right one. |
| Table tool | The on-screen grid used for “Organize” and “Present” items. |
| Graph plotter | The tool for setting scales, plotting points and drawing a line of best fit. |
| Drawing canvas | The tool for building circuit diagrams from standard symbols. |
| Measuring tool | An on-screen ruler, screen or slider read against a scale. |
| ECF | Error carried forward: a later step using a wrong earlier value can still score. |
| WTTE / ORA | Words to that effect / or reverse argument: equivalent answers are credited. |
| Independent mark | A mark (often the unit or significant figures) awarded whether or not the number is right. |
| Linearising | Plotting a changed quantity (such as T² or 1 ÷ d²) so that a curved relationship becomes a straight line. |
Think like a scientist
Criterion A A village borehole in the Kgalagadi uses a solar-powered pump. On a sunny day it lifts water from 40 m below the surface into a storage tank. The engineer’s data: in one hour the pump lifts 500 kg of water; the solar panels deliver 150 W of electrical power to the pump.
(a) State the energy store of the water that increases as it is lifted. [1]
(b) Outline the energy transfers from the Sun to the water in the tank. [2]
(c) Calculate the gain in gravitational potential energy of the water in one hour. Use g = 9.8 N kg⁻¹. [2]
(d) Calculate the efficiency of the pump. Give your answer to 2 significant figures. [3]
(e) Explain why the pump lifts less water on a cloudy day. [2]
(f) Suggest one reason why the tank is placed higher than the houses it supplies. [1]
Model answer
(a) Gravitational potential energy [1]. State = one term.
(b) Light (radiant) energy from the Sun is transferred to electrical energy in the solar panels [1]; the motor transfers electrical energy to kinetic energy of the pump and then to gravitational potential energy of the raised water, with some thermal energy wasted [1]. Two energy forms are needed for each transfer (Physics May 2026).
(c) ΔEp = mgΔh
ΔEp = 500 kg × 9.8 N kg⁻¹ × 40 m
ΔEp = 196 000 J (1.96 × 10⁵ J) [2]
(d) Energy in = P × t
Energy in = 150 W × 3600 s
Energy in = 540 000 J [1]
Efficiency = useful energy out ÷ total energy in × 100
Efficiency = 196 000 J ÷ 540 000 J × 100
Efficiency = 36.3 %, which is 36 % to 2 s.f. [1 calculation, 1 significant figures]
(e) Less light energy reaches the panels each second, so they deliver less electrical power [1]; the pump then does less work each second, so less mass of water gains the same gravitational potential energy in an hour [1].
(f) Water flows from the tank to the houses under gravity, so no pump is needed at night or when it is cloudy (the stored GPE provides the pressure) [1].
Probe deeper — exam-style questions
Attempt every question before opening the answer. Marks in brackets show what a full answer is worth.
State the length of the MYP Physics eAssessment and the approximate number of marks for each criterion.
Reveal answer
120 minutes (2 hours) [1]; about 25 marks for each of Criteria A, B, C and D, 100 in total [1].
Red light has a wavelength of 750 nm and travels at 3.00 × 10⁸ m s⁻¹. Calculate its frequency, in scientific notation.
Reveal answer
750 nm = 7.50 × 10⁻⁷ m
f = v ÷ λ
f = 3.00 × 10⁸ m s⁻¹ ÷ 7.50 × 10⁻⁷ m
f = 4.00 × 10¹⁴ Hz [2]
This is May 2023 Q2d; the May 2025 report found many students “failed to convert 550 nm into metres” in the same kind of item.
Distinguish between “describe” and “explain” using the graph of pressure against volume for a fixed mass of gas at constant temperature.
Reveal answer
Describe: as the pressure increases, the volume decreases; doubling the pressure halves the volume (inverse proportion) [1].
Explain: in a smaller volume the particles hit each square metre of wall more often, so the force per unit area — the pressure — is greater [1].
A design question worth 14 marks has six bullets. State how long to spend, how to lay out the answer, and one thing to check before moving on.
Reveal answer
About 17 minutes (1.2 minutes per mark) [1]. Answer under the bullets in order, as separate sections, because the markscheme follows them [1]. Check: five values of the IV and three repeats with a mean are stated; every control has a value; the DV is read from a named instrument [1].
Explain what “ECF” means and why it is a reason to show working in a multi-step calculation.
Reveal answer
Error carried forward: when an earlier value is wrong, a later step that uses it correctly can still earn its marks [1]. The examiner can only see a correct method if the working is shown; a bare wrong number scores nothing [1].
A 0.050 kg mass is lifted 95.0 cm. A student calculates 0.050 × 9.81 × 95.0 = 46.6 J. The markscheme gave 1 of 2 marks for this. Explain why, and give the correct value.
Reveal answer
The equation was right (1 mark) but the height was not converted to metres, so the answer is 100 times too big [1].
ΔEp = mgΔh
ΔEp = 0.050 kg × 9.81 N kg⁻¹ × 0.950 m
ΔEp = 0.466 J (November 2022 Q6a)
7. A paper’s items are worth: eleven short items totalling 24 marks, a data question of 18, a design of 14, a data question of 14, a short media question of 8, a discuss-and-evaluate question of 13, and two final items totalling 9. Build a timed plan with 5 minutes to read and 5 to check, and justify one change for a slow typist.
Reveal answer
Marks total 24 + 18 + 14 + 14 + 8 + 13 + 9 = 100; 110 minutes of working time gives 1.1 minutes per mark [1].
Short items: 24 × 1.1 ≈ 26 min
First data question: 18 × 1.1 ≈ 20 min
Design: 14 × 1.1 ≈ 15 min
Second data question: 14 × 1.1 ≈ 15 min
Media question: 8 × 1.1 ≈ 9 min
Discuss and evaluate: 13 × 1.1 ≈ 14 min
Final items: 9 × 1.1 ≈ 10 min [2 for a complete plan of about 110 minutes]
A slow typist should answer the short items tersely (state = a word or value) and move those minutes to the design and the discussion, which are marked point by point and need the most typing [1].
8. The grade 7 boundary in Physics was 82 marks in May 2023, 76 in May 2025 and 75 in May 2026. A student scores 22 on Criterion A, 19 on B, 18 on C and 13 on D. Calculate the total and the marks missing for a 7 in each session, and explain which criterion offers the cheapest marks, using the reports.
Reveal answer
Total = 22 + 19 + 18 + 13
Total = 72 marks [1]
Short of a 7 in May 2023: 82 − 72 = 10 marks
Short of a 7 in May 2025: 76 − 72 = 4 marks
Short of a 7 in May 2026: 75 − 72 = 3 marks [1]
Criterion D is the cheapest to raise: 13 of 25 is lost mostly by structure [1]. The Physics reports say missing conclusions cost “a possible 2 marks” (May 2025) and that “conclusions often summarised information rather than weighing evidence” (May 2026), so balanced points with physics support and a weighed appraisal could add 5–8 marks with no new physics [1].
Summary
- The Physics eAssessment is 120 minutes and 100 marks, about 25 for each of Criteria A–D; papers have eight questions, with a long design question in the middle and a long discuss-and-evaluate question at the end.
- The tools — calculator, formula sheet, symbols, table tool, graph plotter, drawing canvas and measuring tool — each have a trap: missing units and superscripts, unconverted prefixes, units in every cell, uneven scales, voltmeters in series.
- Spend about 1.2 minutes per mark; protect the 27–30 marks in the design and discussion questions.
- The command term sets the depth: state a fact, outline two linked points, describe with values, explain the mechanism, calculate with working and unit, evaluate and discuss both sides with a judgement.
- Markschemes use ECF, WTTE, ORA, independent unit and precision marks, gated marks and “do not accept” — show working, convert first, and write the unit every time.
Next time → Criterion A across the whole course: a topic-by-topic checklist of everything the Physics eAssessment can ask, with a retrieval question for each.