- #1
Gogsey
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1. The dispersive power of glass is defined as the ratio(nf-nc)/(nd-1) where c, d and f are the frauhofer wavelengths. Find the approximate group velocity in glass whose dispersive power is 1/30 and nd =1.5
2. A soap film is formed suing a rectangular wire frame and held in a vertial plane. When illuminated normally by laser light at 632.8nm, one sees a series of localized interference fringes that measure15 per cm. Explain their formation.
Ok so for 1, there is a n equation for another problem that is ued to calculate all the n-values, but I'm not sure if its used in all cases or just in that problem. It is n(\lambda) = 1.5255 + (4825)/\lambda. Also don't really know how these numbers relate to calculating the group velocity if its Vg = Vp(1-(k/n)(dn/d\lambda))
As for 2, I really don't have any idea. Don't know where to start. Wouldn't mind a wee nudge in the right direction.
2. A soap film is formed suing a rectangular wire frame and held in a vertial plane. When illuminated normally by laser light at 632.8nm, one sees a series of localized interference fringes that measure15 per cm. Explain their formation.
Ok so for 1, there is a n equation for another problem that is ued to calculate all the n-values, but I'm not sure if its used in all cases or just in that problem. It is n(\lambda) = 1.5255 + (4825)/\lambda. Also don't really know how these numbers relate to calculating the group velocity if its Vg = Vp(1-(k/n)(dn/d\lambda))
As for 2, I really don't have any idea. Don't know where to start. Wouldn't mind a wee nudge in the right direction.
