The figure shows the path of a ray of light through a prism in two positions (angles in degrees)…
Physics20252 marksNumerical
The figure shows the path of a ray of light through a prism in two positions (angles in degrees): on the left the angles of incidence and emergence and the angle of deviation are marked; on the right the ray passes through symmetrically.
Calculate the refractive index of the material of the prism.
Figure 55
Answer
Answer
Official answer key
From the first diagram, $i + e = A + d$, $A = 53 + 42 - 35 = 60^\circ$
From the second diagram, the angle of minimum deviation $= 2i - A = 30^\circ$
Refractive index $= \frac{\sin\frac{A+d}{2}}{\sin\frac{A}{2}} = \frac{\sin 45}{\sin 30} = 1.414$
