Optics Question 560
Question: $ V _{o} $ and $ V _{E} $ represent the velocities, $ {\mu _{o}} $ and $ {\mu _{E}} $ the refractive indices of ordinary and extraordinary rays for a doubly refracting crystal. Then
[KCET 2002]
Options:
A) $ V _{o}\ge V _{E},\ \ {\mu _{o}}\le {\mu _{E}} $ if the crystal is calcite
B) $ V _{o}\le V _{E},\ \ {\mu _{o}}\le {\mu _{E}} $ if the crystal is quartz
C) $ V _{o}\le V _{E},\ \ {\mu _{o}}\ge {\mu _{E}} $ if the crystal is calcite
D) $ V _{o}\ge V _{E},\ \ {\mu _{o}}\ge {\mu _{E}} $ if the crystal is quartz
Show Answer
Answer:
Correct Answer: C
Solution:
In double refraction light rays always splits into two rays (O-ray & E-ray). O-ray has same velocity in all direction but E-ray has different velocity in different direction. For calcite me < m0
Therefore ve > v0 For quartz me > m0
Therefore v0 > ve
