β=dλD
β′=d′λD′
D′=2D,d′=2d
β′=2dλ×2D=d4λD
β′=4β
Fringe width becomes 4 times.
In Young’s double slit experiment, if the separation between coherent sources is halved and the distance of the screen from the coherent sources is doubled, then the fringe width becomes:
Held on 30 Apr 2020 · Verified 9 Jul 2026.
half
four times
one-fourth
double
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