Q. If the source of light used in a Young’s double slit experiment is changed from red to violet :

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If the source of light used in a Young’s double slit experiment is changed from red to violet :

Solution:

$beta=frac{lambda cdot D}{d}$

$lambda_{R} >lambda_{V}$

$beta_{R}=frac{lambda_{R} D}{d}$

and $beta_{v}=frac{lambda_{V} D}{d}$

$beta_{R} >beta_{v}$

Fringe pattern will shrink.