Path difference
What Path difference means in Physics A-Level, as defined for AQA, OCR.
Definitions of Path difference
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Reference: AQA
The extra distance one wave travels compared with another from the same source to a point, determining whether they arrive in step or out of step.
The extra distance travelled by light from the second slit compared with the first of two adjacent slits, equal to d sinθ.
A distance in metres, linked to phase difference by Δφ = 2πΔx/λ, where Δx is path difference and λ is wavelength.
The difference in distance travelled by two waves from their sources to a point.
Determines whether waves from the two sources arrive in phase or out of phase.
Topics that use Path difference
- Diffraction (AQA A-Level)
- Interference (AQA A-Level)
- Superposition (OCR A-Level)
Related terms
- Constructive interference
- Coherence
- Constructive superposition
- Destructive interference
- Destructive superposition
- Grating spacing
- Interference
- Order of the maximum
Using Path difference in the exam
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