OUSTANDING QUESTIONS

[Jordan23]

FROM INSIGHT 09

Light and Matter:
Q2 - When finding wavelength that would exist in emission spectra and not absorbtion spectra, are photons which result from loss of momentum of two colliding emission photons valid?
Q5 - Asked to calculate deBrogile wavelength and got answer of 1.2x10^-11m (same as theres in working of solution) isnt that 0.0112nm not 121nm
Q7 - If one slit is used instead of two doesn't the max gap need to be the same size as two wavelength since, interference will only occur if two wavelets pass through gap, or is the distance between wavelets 0 and two point sources are produced anyway?

For the last question I talked to my teacher, and he said that I should just write the good old VCE crap where wavelength is approximately equal to width, even though for single slit this will hardly produce a fringe pattern and the optimal would be a wavelength slightly under the width gap so there is greater inteference between the light travelling from the two edges of the gap, which act as point sources. However I am still confused what to write as I don't understand how the VCE way would be an acceptable answer since a fringe pattern would hardly be observed? Could someone explain the interference of single slit in terms of what is required on the VCE course

[appianway]

Look, there are lots of mistakes in Insight 09, so your answer for question 5 is probably right.

As for the others...

2: I'm not sure if photons can be created from collisions with other photons (I always thought not, but hey), but if you're going to argue that the new photon has a different wavelength, you have to consider that the energies (and hence frequencies) of the other photons will change due to the conservation of energy. And that'd only apply if photons could be created through collisions anyway.

7: The intensity pattern is more like a probability distribution - experiments have used individual photons (I think?) and the same pattern's been observed. Therefore you don't have to have 2 photons travelling through the slit simultaneously - the same result should be obtained if only one goes through. That aside, the slit width essentially refers to the extent of diffraction - I think that diffraction occurs around all objects (irrespective of size), but the size of this diffraction depends on the relative sizes of the obstacle/gap and the wavelength.

[disco]

hey buddy can u post insight 09 up pleasee

[TonyHem]

hey buddy can u post insight 09 up pleasee

It is up. You just have to find it.


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