Constructive interference
What Constructive interference means in Physics A-Level, as defined for AQA, OCR.
Definitions of Constructive interference
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Reference: OCR
Gives maximum amplitude when the waves arrive in phase, with phase difference zero or a whole number of cycles and path difference zero or a whole number of wavelengths.
Where waves arrive in phase, as when crest meets crest or trough meets trough, and reinforce to give a bright fringe.
Occurs when the path difference between light from two adjacent slits equals a whole number of wavelengths, nλ.
Occurs where path differences are whole numbers of wavelengths, producing bright fringes.
Topics that use Constructive interference
- Diffraction (AQA A-Level)
- Interference (AQA A-Level)
- Significance of Young’s double slits experiment (A-level only) (AQA A-Level)
- Superposition (OCR A-Level)
Related terms
- Destructive interference
- Path difference
- Coherence
- Constructive superposition
- Destructive superposition
- Grating spacing
- Interference
- Order of the maximum
Using Constructive interference in the exam
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