SI units and conversions
What SI units and conversions means in Physics A-Level, as defined for OCR.
Definitions of SI units and conversions
Exam boards and our study guides word this term in slightly different ways. Learn the version your board uses.
Check what you remember
Read the wording for your board, then hide it and explain SI units and conversions in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: OCR
All quantities should be converted to SI units first, for example converting a velocity given in km h⁻¹ to m s⁻¹ by dividing by 3.6 before using P = Fv.
The unit of moment is the newton metre (N m), and distances must be converted from centimetres to metres before calculating.
Topics that use SI units and conversions
- Equilibrium (OCR A-Level)
- Power (OCR A-Level)
Related terms
- Couple
- Efficiency
- Equilibrium conditions
- Force and motion
- Free-body diagrams
- Mechanical power
- Moment of a force
- Perpendicular distance between lines of action
Using SI units and conversions in the exam
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