A prism has a refracting angle of 30^circ and | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) Since the incident ray retraces its path,it must strike the silvered face of the prism normally (at an angle of $90^\circ$).In the triangle formed

Vedclass · Accepted Answer

$45$

Vedclass · Answer

(D) Since the incident ray retraces its path,it must strike the silvered face of the prism normally (at an angle of $90^\circ$).In the triangle formed by the prism,let the vertices be $A, B, C$ and the point of incidence be $D$ on face $AC$,and the point on the silvered face be $E$. In $	riangle AED$,the angles are $30^\circ$,$90^\circ$,and $\angle ADE$.Sum of angles in $	riangle AED = 180^\circ$.$30^\circ + 90^\circ + \angle ADE = 180^\circ \Rightarrow \angle ADE = 60^\circ$.The angle of refraction $r$ is the angle between the normal at $D$ and the refracted ray $DE$. Since the normal is perpendicular to the face $AC$,we have $\angle r + \angle ADE = 90^\circ$.$\angle r = 90^\circ - 60^\circ = 30^\circ$.Applying Snell's Law at the surface $AC$:$1 \cdot \sin i = \mu \cdot \sin r$$\sin i = \sqrt{2} \cdot \sin 30^\circ$$\sin i = \sqrt{2} \cdot \frac{1}{2} = \frac{1}{\sqrt{2}}$.Therefore,$i = 45^\circ$.

$A$ prism has a refracting angle of $30^\circ$ and a refractive index of $\mu = \sqrt{2}$. One of its faces is silvered. $A$ ray of light incident on the other face retraces its path. What is the angle of incidence in degrees?

Similar Questions

An equilateral prism deviates a ray through $40^{\circ}$ for two angles of incidence differing by $20^{\circ}$. The possible angles of incidence are:

When a glass prism of refracting angle $60^\circ$ is immersed in a liquid,its angle of minimum deviation is $30^\circ$. The critical angle of glass with respect to the liquid medium is......$^\circ$

Define incidence angle,emergence angle,and deviation angle in the context of a prism.

The refractive index of a prism with apex angle $A$ is $\cot(A/2)$. The angle of minimum deviation is:

Vedclass Test Series

Exam Paper Generator

Online Exam Module