unit conversion
What unit conversion means in Physics GCSE, as defined for AQA, OCR.
Definitions of unit conversion
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Reference: AQA
Changing values into the right units before substituting, such as converting energy from kilojoules into joules and lengths into metres.
Before substituting, convert every quantity to the stated SI units, so minutes or hours become seconds and distances stay in metres.
Half-lives given in different units, such as days against years, must be converted to a common unit before comparing two half-lives.
Converting centimetres to metres and milliamperes to amperes before substituting, since most marks are lost on units.
A force in kilonewtons or a distance in centimetres has to be converted to newtons and metres before substituting.
Changing a wavelength written in centimetres into metres before it is used in wave speed = frequency × wavelength.
Topics that use unit conversion
- Different half-lives of radioactive isotopes (AQA GCSE)
- Fleming's left-hand rule (HT only) (AQA GCSE)
- Forces and elasticity (AQA GCSE)
- Properties of waves (AQA GCSE)
- Work done and energy transfer (AQA GCSE)
- Motion (OCR GCSE)
Related terms
- displacement
- rearrangement
- Acceleration
- Accurate reading of scales
- activity against duration
- activity and half-life
- amplitude
- Appropriate apparatus selection
Using unit conversion in the exam
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