Measurement is the base of SPM Physics. It has four skills: converting units, separating scalars from vectors, reading instruments, and plotting graphs.
This page sits under SPM Physics. It shows the order to study, one short example, and where to start.
How do the lessons connect?
Units come first, because every reading and graph carries one. Vectors follow, because they change how you add quantities later in forces and motion.
- Converting SI prefixes and units
- Distinguishing scalar and vector quantities
- Reading measuring instruments and uncertainty
- Plotting a graph with appropriate scale and units
A further section, uncertainty and practical-data reasoning, trains you to judge data once the core skills are secure.
What does one example look like?
An original spring experiment: a student hangs masses on a spring and measures the extension with a ruler. The ruler reads 45 mm for one mass.
Conversion: 45 mm = 4.5 cm = 0.045 m. Reading: the ruler resolution is 1 mm, so 45 mm is written with that precision. Graph: each force and extension pair becomes one point, and the gradient of the best-fit line gives the spring constant.
One small experiment needed all three skills, and later topics use them in the same way.
Who should start where?
- Your answers are off by factors of ten: start with units.
- You mix up which quantity needs a direction: start with scalars and vectors.
- Your readings disagree with the mark scheme: start with instruments.
- You lose marks on graph paper: start with graph plotting.
When all four feel secure, try the measurement practice set.
Need a teacher to check the habit?
A teacher can watch you read an instrument and plot a graph in one session and spot which habit causes the slips. If you would like that, see online one-to-one Physics tuition and the one-hour trial class (from RM50).