SI Units

  • SI units and prefixes
  • the estimation of physical quantities
  • the limitations of physical measurements
  • estimating uncertainty

A secure understanding of these fundamental concepts which underpin the whole of physics is crucial for all students. They need to be able to look at an answer and know if the answer is too big, too small or just about right. This is a concept that a lot of students struggle with. Start by teaching the prefixes required, and the sizes that these relate to, before introducing the SI units. It is useful for students to be able to derive these. Estimation and limitations complete the sequence.

Students should be familiar with orders of ten and SI units from their work at GCSE. They may not have come across uncertainty or deriving SI units previously.

Whilst this list provides a source of information and ideas for experimental work, it is important to note that recommendations can date very quickly. Do NOT follow suggestions which conflict with current advice from CLEAPSS or recent safety guides. eLibrary users are responsible for ensuring that any activity, including practical work, which they carry out is consistent with current regulations related to Health and Safety and that they carry an appropriate risk assessment. Further information is provided in our Health and Safety guidance.