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sean
Posts:
6
Registered:
12/13/04


frequency question
Posted:
Feb 2, 2005 5:09 AM


I would like to get some feedback on a couple of maths problems I have been discussing with others recently where we cant agree on the results. Problem A) There are two trains of waves travelling in the same direction towards an observor who is at point x. Wavelength A is longer than wavelength B and thus has a higher frequency observed at x provided the two are travelling at the same speed. My question to anyone on this newsgroup is if the speed of wavelength B (the shorter wavelength) were reduced relative to the speed of wavelength A would it be possible to arrive at a situation where the observed frequency of the two at x would appear to be the same? That is: would it be possible to reduce the speed of the shorter wavelength by a certain amount so as to make its observed frequency appear to be equivelent to the observed frequency of the longer wavelength?
Problem B) In this formula below... I(t) = Imax * ( fR((ttmax)/s(1+z)) + b ). where s is known to be 1.1 and z is known to be 0.1 the result of s(1+z) part of the formula is 1.1 and indeed as the formula above is a fitting formula a full calculation using known t tmax and I etc also gives s =1.1
However for a second example where z=0 ,s is unknown and t, tmax and I are unknown is it possible to calculate s at all from just the above information only and if so would the result be s=1.21?
thanks ahead Sean



