Question

Does the path length difference delta l increase or decrease as you move from one bright fringe of a two-slit experiment to the next bright fringe farther out? increase decrease What is delta l of the third bright fringe outside of the central bright fringe in terms of the wavelength lambda of the light? ________ lambda

Answer 1

a) path difference(Δl)=m $\lambda$ ,where m is order

first bright fringe means m=1 and second order bright fringe means m=2 hence m is increase

path difference propotional to m

then path difference is also increase

b) path difference(Δl)=m $\lambda$ ,where m is order

third order bright fringe means m=3

$\lambda$ =Δl/3.......answer