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Hi, would it be possible to explain to me how does wave length, phase difference and path difference all link as I'm struggling with calculations involving these three things.
When 2 or more waves meet they combine. To know the resultant wave you need to know whether the waves are 'in step'..in phase or 'out of step' ...out of phase, or something in between.Hi, would it be possible to explain to me how does wave length, phase difference and path difference all link as I'm struggling with calculations involving these three things.
Do you have a particular question that needs solving..... 2 slits, diffraction grating..... EtcI understand wavelength is the distance between a point on a wave and the same point on the next cycle.
Path Difference, how much a wave lags behind another usually measured in meters.
Phase Difference how much a wave is behind or in front of another wave usually measured in radians or degrees.
I clearly have a major misunderstanding as when faced with questions relating all three, I don't know how to begin to answer the question.
When two waves take different paths, the length of those paths can be measured in wavelengths and the path difference would be the difference between those path lengths. Usually measured in wavelengths.Path Difference, how much a wave lags behind another usually measured in meters.
Given the path difference of two waves, assuming they were in sync to start with, you can figure out their phase difference from the path difference.Phase Difference how much a wave is behind or in front of another wave usually measured in radians or degrees.
The geometrical lengths of the paths (in m) is not the only thing that counts. If the light travels through more than one medium (glass/air for instance) the number of wavelengths will be different, depending on the proportion of glass and air along the path. So it's the transit times that actually affect the relative phases where the waves interfere. That means the path difference should be calculated in terms of wavelengths of the wave (and it will be different for different wavelengths).Path Difference, how much a wave lags behind another usually measured in meters.
A progressive wave (a traveling wave) will have a phase that varies with position and time, so I guess that's what he means by "different".Here is a slide from my lecturers power point, i'm having trouble understanding what he means by phase "different" in progressive transverse waves and "in phase between nodes, out of phase in adjacent nodes".
A simple sinusoidal wave can be writtenWould you be able to further explain what you mean by the phase varies with position and time? What is the phase different relative to?
What does he mean by this?:"in phase between nodes, out of phase in adjacent nodes".
Hi this formula assumes that the wavelength of the two waves are the same, how would I deal with calculations where both wavelengths are different?The geometrical lengths of the paths (in m) is not the only thing that counts. If the light travels through more than one medium (glass/air for instance) the number of wavelengths will be different, depending on the proportion of glass and air along the path. So it's the transit times that actually affect the relative phases where the waves interfere. That means the path difference should be calculated in terms of wavelengths of the wave (and it will be different for different wavelengths).
The path difference can be many wavelengths in extent but the phase difference (what you use to calculate the resulting amplitude after the interference) will be between 0° and 360°.