SI Base Units Relationships Poster (SP 1247)

Credit: E. Tiesinga, K. Dill, D. Newell/NIST

SI Base Units Relationships Poster (SP 1247)
Edition: 2020

Summary

This colorful resource provides a printable SI unit diagram, which illustrates the relationships between the SI base units and derived units with special names. This chart may be printed on any paper size but is recommended to be size 215.9 mm x 279.4 mm (8.5 in x 11 in). This resource is an interactive method to engage students in learning about the relationships of SI units. The diagram is aligned with the BIPM SI Brochure, 9th edition and NIST SP 330, The International System of Units (SI), 2019 edition.

The traditional SI base unit symbols are shown within rectangle shapes, with the unit name shown above the corresponding rectangle. The derived units with special names are shown in circle shapes, with the unit symbol and name within the circle. An expression for the derived unit in terms of other units shown in parenthesis. Derived units without special names are not illustrated. In the diagram, the derivation of each derived unit is indicated by arrows that bring in units in the numerator (solid lines) and units in the denominator (broken lines), as appropriate. The unit "degree Celsius,'' which is equal in magnitude to the unit "kelvin," is used to express Celsius temperature t, defined by the quantity equation t = T - T0, where T0 = 273.15 K, the ice point. This equality is indicated in the diagram by the symbol K in the °C circle. The numerical value of a Celsius temperature t expressed in degrees Celsius is given by the equation below "CELSIUS TEMPERATURE.'' A difference or interval of temperature may be expressed in kelvins or in degrees Celsius.

Did you know that you can obtain a free set of metric education resources for use in your classroom? Contact the NIST Metric Program at TheSI [at] nist.gov (TheSI[at]nist[dot]gov) and include your name, school, subject, grade level, phone number, and U.S. mailing address. Publication requests may also be made using the OWM Contacts System. The NIST SI Teacher Kit contains a curated collection of instructional measurement resources. A metric ruler is a valuable tool for science, technology, engineering, art, and math (STEAM) classrooms.

Learning Objectives

• Recognize SI units of measure.
• Observe SI unit relationships.
• Develop SI unit familiarity.

Materials

• Required
  • Digital file.
  • Paper.
  • Printer.
• Recommended
  • 215.9 mm x 279.4 mm (8.5 in x 11 in) office size paper.

Safety

• Use caution when handling paper edges to prevent injury.

Teaching Tips

• Use the Top 10 Tips for Teaching the Metric System. 
  • Measurement concepts are meaningfully established through hands-on activities. Application, not memorization, is the key to success! 
  • Practice building proficiency and confidence in making measurements. Measurement involves doing.
  • Develop reference points. How long? How big? How small? It’s important for students to gradually develop an intuitive feeling for the magnitude of commonly used metric units, including the millimeter (mm) and centimeter (cm). 
• Explain the SI base units and prefixes. Describe how the SI base units are used to realize the SI derived units with special names.
•  Use the SI Relationship Poster (SP 1247) when playing game activities described in the SI Base Units Card Deck (SP 1297).

Classroom Connections

• SI Units
• SI Redefinition Constants
• Redefining the World’s Measurement System
• SI Prefixes
• Metric Bookmark
• Metric Children’s Activity Card
• Metric Conversion Card (SP 365)
• Metric Pyramid (LC 1140)
• Metric Ruler (SP 376)
• SI Units Card Deck (SP 1297)
• SI Measurement System Chart
• Measurement League: Guardians of the SI Superhero Card Set

Additional Resources

• National Metric Week
• Becoming Familiar with SI
• Everyday Estimation
• Metrication FAQs
• Education Metrication
• SI Education and Training
• SI Publications
• Understanding Metric
• Writing with Metric Units
• NEST-R (STEM Registry)
• NIST Education Resources