Physics GCSE
focal length
What focal length means in Physics GCSE, as defined for AQA.
Definition of focal length
Check what you remember
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Reference: AQA
The distance from the lens to the principal focus, measured from the centre of the lens to the principal focus.
Topics that use focal length
- Lenses (physics only) (AQA GCSE)
Related terms
- always virtual
- arrowheads in or out
- converging and diverging
- diverging lens
- dotted projections
- magnifying glass
- matched comparison
- real image
Using focal length in the exam
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