Physics 0625 · syllabus 1.1
Cambridge IGCSE Physics 0625 — Physical quantities and measurement techniques topical past papers
Measuring lengths, volumes and time intervals, timing many oscillations to find a period, and, on the Extended route, scalars, vectors and their resultants.
- Questions
- 464
- Years
- 2009–2026
- With mark scheme
- 99%
- Questions 2022–2026
- 149
Anyone can browse these pages. Opening the questions and their mark schemes takes a free Momentum account.
What Physical quantities and measurement techniques covers
Every measurement in physics is a number with a unit, taken with an instrument that suits the job. Lengths come from a ruler or metre rule, the volume of a liquid from a measuring cylinder read at the bottom of the meniscus with your eye level with the surface, and time intervals from a clock, a stopwatch or a digital timer. Each reading is recorded with its unit and to the precision the instrument allows, such as the nearest millimetre on a metre rule.
When one item is too thin or one event too quick to measure well, measure many together and divide. The thickness of a sheet of paper comes from a stack of a hundred sheets, and the period of a pendulum, the time for one complete swing there and back, comes from timing twenty swings and dividing by twenty. Starting and stopping a stopwatch by hand adds an error of a few tenths of a second, and spreading that error over many swings makes the result far more reliable than a single timing.
Extended candidates also sort quantities into scalars, which have size only, and vectors, which have size and direction: mass, time, distance, speed, energy and temperature are scalars, while force, weight, velocity, acceleration, momentum and the strengths of electric and gravitational fields are vectors. Two forces or two velocities at right angles combine into a single resultant, found by scale drawing or with Pythagoras' theorem and trigonometry. Measurement is tested on Papers 1 to 4, and it is the foundation of every practical question in Papers 5 and 6.
In the syllabus
The headings this topic has in the Cambridge International 2026–2028 syllabus, as the board prints them.
- 1.1 Physical quantities and measurement techniques
What you should be able to do
- Choose a suitable instrument for a length, a liquid volume or a time interval, and read it correctly
- Read a measuring cylinder at the bottom of the meniscus, with your eye level with the liquid surface
- Find a small length or a short time by measuring a multiple and dividing, as for the period of a pendulum
- Explain why timing many oscillations gives a more reliable period than timing one
- Say whether a quantity is a scalar or a vector (Extended)
- Find the resultant of two forces or two velocities at right angles, by calculation or by scale drawing (Extended)
Key ideas
- Period = total time ÷ number of complete oscillations
- Thickness of one item = thickness of the stack ÷ number of items
- Scalars have magnitude only; vectors have magnitude and direction (Extended)
- Resultant of perpendicular vectors a and b: √(a² + b²), at an angle θ to a where tan θ = b/a (Extended)
- 1 m = 100 cm = 1000 mm; 1 m³ = 1 000 000 cm³; 1 dm³ = 1000 cm³
How Physical quantities and measurement techniques has been examined
From 2022 to 2026, Physical quantities and measurement techniques was on Paper 6 · Alternative to Practical in 10 of 14 exam series, worth about 15% of that paper’s marks.
| Paper | Questions | Share of marks | Series |
|---|---|---|---|
| Paper 1 · Multiple Choice (Core) | 63 | 5% | 14 of 14 |
| Paper 2 · Multiple Choice (Extended) | 45 | 4% | 13 of 14 |
| Paper 3 · Theory (Core) | 17 | 5% | 9 of 14 |
| Paper 4 · Theory (Extended) | 6 | 2% | 3 of 14 |
| Paper 6 · Alternative to Practical | 18 | 15% | 10 of 14 |
Momentum’s own count, over the questions in its bank for these years: a series is one exam session, every zone included, and a question filed under two chapters counts in both. Median marks per question: 1. The bank files this topic together with neighbouring ones, so these figures count every question in its chapters, including some on those topics.
Filed in Momentum under: Measurements and Units.
A worked example
A boat points straight across a river and moves through the water at 3.0 m/s, while the current carries it downstream at 1.2 m/s. Find the size and direction of the boat's resultant velocity.
- The two velocities are at right angles, so the resultant is the hypotenuse of a right-angled triangle
- Size: √(3.0² + 1.2²) = √(9.00 + 1.44) = √10.44 = 3.23 m/s
- Direction: tan θ = 1.2 / 3.0 = 0.40, so θ = 21.8° downstream of the line straight across
- Check: the resultant is larger than either velocity but smaller than their sum, 4.2 m/s
Answer: 3.2 m/s, at about 22° downstream of straight across
Written by Momentum for this page, with its own numbers; it is not taken from a past paper.
Mistakes that cost marks
- Counting each pass through the middle as a complete oscillation — one oscillation runs from one side to the other and back again, so counting passes gives a period half the true value
- Reading a measuring cylinder at the top of the meniscus, or with the eye above or below the surface — the reading belongs at the bottom of the meniscus with the eye level, or parallax makes it wrong
- Measuring from the end of a ruler rather than from its zero mark — the end may be worn or set back from the zero, so every length comes out wrong by the same amount
- Adding perpendicular forces as if they acted along one line — forces of 3.0 N and 4.0 N at right angles have a resultant of 5.0 N, not 7.0 N
- Calling speed or mass a vector — neither has a direction; velocity is speed in a given direction, and weight, a force, is a vector although mass is not
Exam technique
- When describing a measurement, name the instrument, say exactly what you read and how, and say that you repeat the reading and take an average
- Show the division in your working when you measure a multiple: 20 oscillations in 30.4 s gives a period of 30.4 ÷ 20 = 1.52 s
- For a scale drawing, state the scale, draw the two vectors head to tail at right angles, and measure both the length and the angle of the resultant
- Record each reading with its unit and with as many decimal places as the instrument supports, and no more
Practising in Momentum
- Every question in a chapter as one list, from every paper and year in the bank, newest first or shuffled.
- Each question turns over to its own part of the mark scheme, where the board published one.
- Narrow by paper, year, session, zone and marks, and star the questions worth keeping.
- Pick chapters, a number of questions and a time, and the exam builder draws a mock to sit and mark.
Past-paper questions and mark schemes are the copyright of Cambridge International. Momentum shows them to signed-in learners for revision and does not publish them on these pages.