Physics A-Level
Central obstruction
What Central obstruction means in Physics A-Level, as defined for AQA.
Definition of Central obstruction
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Reference: AQA
The secondary mirror causes some obstruction of the incoming light.
Topics that use Central obstruction
- Reflecting telescopes (A-level only) (AQA A-Level)
Related terms
- Aperture stop
- Chromatic aberration
- Convex secondary mirror
- Folded optical path
- Formation of a real intermediate image
- Optical ray construction and labelling
- Parabolic mirror
- Reflection at curved and plane surfaces
Using Central obstruction in the exam
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