Physics A-Level
Point-source assumption
What Point-source assumption means in Physics A-Level, as defined for AQA.
Definition of Point-source assumption
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Reference: AQA
The source must be small compared with the distance at which it is observed, so that rays are effectively radial.
Topics that use Point-source assumption
Related terms
- Black body
- Intensity–wavelength curve
- Inverse-square law
- Peak wavelength
- Stefan constant
- Stefan's law
- Wien's displacement law
- Black-body radiator
Using Point-source assumption in the exam
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