Phase difference
What Phase difference means in Physics A-Level, as defined for AQA, OCR.
Definitions of Phase difference
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Reference: OCR
An angle in radians, linked to path difference by Δφ = 2πΔx/λ, where Δx is path difference and λ is wavelength.
A comparison of two points or two waves, measured in degrees or radians, where a full cycle is 360° or 2π rad.
Determined by the path difference between the recombining waves and therefore fixes the fringe positions.
A comparison of two oscillations of the same frequency, expressed in radians or degrees.
How far one wave is ahead of another in its cycle, measured in degrees or radians.
A comparison of two points measured in radians, degrees or fractions of a cycle.
Topics that use Phase difference
- Progressive waves (AQA A-Level)
- The Michelson-Morley experiment (A-level only) (AQA A-Level)
- Simple harmonic oscillations (OCR A-Level)
- Superposition (OCR A-Level)
- Wave motion (OCR A-Level)
Related terms
- Amplitude
- Displacement
- Frequency
- Period
- Wavelength
- absolute motion
- Angular frequency
- Classical Galilean velocity addition
Using Phase difference in the exam
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