Unit conversions
Convert quantities with exact unit ratios, track cancellation through compound units, and apply the correct powers to area and volume. Distinguish temperature readings from differences, check dimensions and context, and retain measurement uncertainty when reporting.
Key knowledge
For units connected by a scale factor, multiplying the unit by a factor divides the numerical value by that factor. Celsius temperature values instead require an offset from kelvin values.
Values and equations
1 km = 1000 m
- km
- Kilometre
- m
- Metre
Conditions and scope
- The scale-factor rule applies to units of the same kind of quantity.
- For Celsius values, t/°C = T/K − 273.15; temperature intervals have equal numerical values in K and °C.
Sources · 9
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
National Institute of Standards and Technology (NIST)2 sources
- TIMES Module 10 · Introduction to MeasurementAustralian Mathematical Sciences InstituteTeaching resource
- Grade 10 Physics · Teacher Guide (2018 trial edition)Palestinian Ministry of Education and Higher Education · Curriculum CentreTeaching resource · PDF
- O Sistema Internacional de Unidades (SI) · 2ª edição luso-brasileiraInmetro and Instituto Português da QualidadeReference guide · PDF
Evidence and review
SI Brochure 2.3.1 (kelvin/Celsius), chapter 3 and 5.4.1; NIST prefix factors.
2026-10-10 · Scale conversion and Celsius exception only; conversion does not improve the original measurement uncertainty.
Foundational review
2026-10-10 · Fresh primary-source inspection of the complete compact record, including every statement, equation, quantity and material condition, followed by independent AI editorial review. This check does not certify all linked lessons or every passage of every cited publication.
Sources from other places
Scope or convention differs
Celsius numerical values require an offset; kelvin/Celsius intervals have equal numerical values.
The Portuguese standard shares the original BIPM family; it is regional implementation, not independent evidence.
Inmetro and Instituto Português da Qualidade
- O Sistema Internacional de Unidades (SI) · 2ª edição luso-brasileira Brazil and PortugalPortugueseShared standard
§2.3.1 Kelvin and degree Celsius, PDF p.25; §5.4.1
- O Sistema Internacional de Unidades (SI) · 2ª edição luso-brasileira
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