Physics - Geometrical Optics Question with Solution | TestHub

Isosceles glass prism $(\mu =1.57)$ with small refracting angles $(\alpha )$ is placed in front of parallel beam of rays incident normally on its base (see figure). The size of the base $2\mathrm{a}=5\mathrm{cm}$. Light falls on a screen at a distance of 100 cm from the prism with a dark patch of width 1 cm near center of screen. Find the value of the refracting angle $\alpha$.