Unit consistency
What Unit consistency means in Physics GCSE, as defined for AQA, OCR.
Definitions of Unit consistency
Exam boards and our study guides word this term in slightly different ways. Learn the version your board uses.
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Reference: OCR
Keeping mass and volume in matching units, for example g and cm³ give g/cm³, and converting to kg/m³ by multiplying by 1000.
Using matching distance units on both sides, so distances can stay in centimetres because the units cancel.
Density in kg/m³, depth in m and pressure in Pa (N/m²) must be kept consistent.
Topics that use Unit consistency
- Moments, levers and gears (physics only) (AQA GCSE)
- Materials (OCR GCSE)
- Pressure (OCR GCSE)
Related terms
- Atmospheric pressure and weight of air
- balanced beam
- Cause-and-effect explanation
- Choosing appropriate apparatus
- Closed systems
- Collisions with container walls
- Comparing pressures at different heights
- Constant temperature and constant average particle speed
Using Unit consistency in the exam
Check the command word and mark scheme for your exact question. After comparing your explanation with the reference, use the term in an answer on the linked topic. This practice does not predict an exam mark.
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