Fresnel's Biprism - Practice Questions & MCQ

- Let the separation between $\mathrm{S}_1$ and $\mathrm{S}_2$ be d and the distance of slits and the screen from the biprism be a and b respectively i.e. $D=(a+b)$. If the angle of the prism is $A$ and the refractive index is $\mu_{\text {then }} d=2 a(\mu-1) A$

$
\therefore \quad \lambda=\frac{\beta[2 a(\mu-1) A]}{(a+b)} \Rightarrow \beta=\frac{(a+b) \lambda}{2 a(\mu-1) A}
$