My friend needed help on the question and when he googled it he got this. I thought I would give an alternative explanation for anyone else in his class who also googled it. heh just helping I suppose...if I was right that is.
In other words: there is a kinetic energy imparted into the block when the bullet collides with it. That kinetic energy is the kinetic energy of the new block-bullet system. Next the block moves a distance d until it reaches a stop. This means that friction does work on it over that distance d...
oh hehe never mind.
as it turns out because the path difference divided by the wavelength is number of fringes that pass I can set up a diagram to evaluate the problem.
Quite simply, the change in distance for the interferometer which has an arm that changes length is just 2L - 2(L-d_m)...
does anyone know how to derive this equation regarding the Michelson interferometer:
d_m = (m[lambda])/2
where d_m is the physical distance of a micrometer division, m is the number of fringes that crosses a screen given some d_m and lambda is the wavelength of the laser used to create the...