Question

Light passes through a pair of very thin parallel slits. The resulting interference pattern is viewed far from the slits at various angles θ relative to the centerline coming outward from the midpoint between the slits. The central bright fringe is at θ=0∘. If the central bright fringe has intensity I0, what is the intensity of the next bright fringe on either side of it?

Answer 1

Answer:

Intensity of the next bright fringe will remain same.

Explanation:

The question is based on Young's double slit experiment, since its about bright fringe, the interference here is constructive.

Young's condition for constructive interference is given by:

dsin$\theta = n\lambda$

where,

d = slits distance from eachother or width of the slits

$\lambda$ = wavelength

n = interferance order

Also, we know that in Young's experiment, the fringe intensity is given by:

$I' = 4Icos^{2}\phi$

where,

$\phi$ = phase difference

Therefore, in absence of phase difference i.e., $\phi = 0$, the intensity of the next bright fringe will not change and it will remain same.