Physics / core
Measurement, units, and experimental standards
Build operational definitions of physical quantities through calibration, uncertainty, traceability, and tests of dimensional reasoning.
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Module 01 core
Measurement, units, and experimental standards
Build operational definitions of physical quantities through calibration, uncertainty, traceability, and tests of dimensional reasoning.
- 01
Define the quantity before measuring it
Distinguish the intended quantity from an instrument indication and construct a measurement model with explicit reference conditions.
28 min - 02
SI units and exact defining constants
Connect units to the constants defining the SI while distinguishing exact definitions from uncertain experimental realizations.
27 min - 03
Test equations with dimensions and rescaling
Use dimensional homogeneity, unit invariance, and limiting cases to reject physical models before fitting experimental numbers.
29 min - 04
From reference standards to a calibration curve
Construct and invert a calibration relation, assess its usable range, and retain uncertainty from standards, fitting, and drift.
31 min - 05
Separate scatter from persistent measurement effects
Distinguish random variation, systematic effects, and Type A or Type B uncertainty evaluation without confusing their classifications.
31 min - 06
Propagate uncertainty with covariance
Use sensitivity coefficients and covariance to distinguish uncertainty amplification from cancellation in sums, differences, and ratios.
34 min - 07
Separate resolution, sensitivity, and usable range
Translate indication steps into input steps and distinguish fine display resolution from low uncertainty, useful sensitivity, and overload limits.
30 min - 08
Precision, accuracy, and a defensible bias correction
Compare repeatability with agreement to a reference and correct an estimated bias while retaining the correction's uncertainty.
30 min - 09
Reduce an experiment with Buckingham Π groups
Construct independent dimensionless groups and use similarity to design comparisons while keeping missing physics and regime limits visible.
35 min - 10
Build a traceable and reproducible measurement result
Document calibration links and uncertainty contributions, then design reproducibility checks that challenge shared blind spots.
33 min