The maximum number of possible interference maxima when slit separation is equal to 4 times the wevelenght of light used in a double slit experiment is

Options

A. 8
B. 4
C. `oo`
D. 9

Explanation

The width of the fringe is `beta=(lambdaD)/(d)`
Given that `d=4lambda,beta=(lambdaD)/(4lambda)=(D)/(4)`.
Normally D is the order of metres (0.5 to 1m?) `beta` is very large .
The number of orders that can be accomodated is less than one for normal screen . No option given.