Physics A-Level
Coherence
What Coherence means in Physics A-Level, as defined for AQA, OCR.
Definitions of Coherence
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Reference: OCR
Waves have a constant phase difference and the same frequency, which is needed for a stable interference pattern.
A property of sources having the same frequency and a constant phase difference.
Waves have a constant phase difference and, in practice, the same frequency.
Topics that use Coherence
- Interference (AQA A-Level)
- Superposition (OCR A-Level)
Related terms
- Constructive interference
- Constructive superposition
- Destructive interference
- Destructive superposition
- Grating spacing
- Interference
- Path difference
- Coherent monochromatic sources
Using Coherence in the exam
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