Physics - Geometrical Optics Question with Solution | TestHub

We know that the angle of deviation depends upon the angle of incidence. If we determine experimentally, the angles of deviation corresponding to different angles of incidence and then plot$\mathrm{i}$(on$\mathrm{x}$-axis) and$\mathrm{\delta }$(on$\mathrm{y}$-axis) we get a curve as shown in the figure.




Clearly, if the angle of incidence is gradually increased from a small value, the angle of deviation first decreases, becomes minimum for a particular angle of incidence and then begins to increase.