How would the angular separation of interference fringes in Young's double slit experiment change when the distance of separation between slits and screen is doubled ?

Explanation

Since `beta=(lambdaD)/(d)`
`therefore beta_(1)=(lambda((D))/(2))/(d)=(1)/(2)(lambdaD)/(d)=(1)/(2)beta`
Hence the angular separation of interference fringes (fringe width) becomes half.