β=dλD=0.5×10−35890×10−10×0.5
=589×10−6m
Distance between first and third bright fringe is 2β=2×589×10−6m
=1178×10−6m
In Young's double slit arrangement, slits are separated by a gap of 0.5mm, and the screen is placed at a distance of 0.5m from them. The distance between the first and the third bright fringe formed when the slits are illuminated by a monochromatic light of 5890Ao is :-
Held on 18 Mar 2021 · Verified 6 Jul 2026.
1178×10–9m
1178×10–6m
1178×10–12m
5890×10–7m
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