please solve QUESTION number 6( b) fast urgently needed - Physics - Ray Optics And Optical Instruments

Question

please solve QUESTION number 6( b) fast urgently needed

Q 6 ( b )       A   l i g h t   r a y
  t r a v e l s   f r o m   m e d i u m   1
  o f   r e f r a c t i v e   i n d e x   μ
1     t o   m e d i u m   2   o f   r
e f r a c t i v e   i n d e x   μ 2 ,   w h e r e
  μ 2   <   μ 1   W r i t e   a n
  e x p r e s s i o n   f o r   c r i t i c a l
  a n g l e   ( i e )   o f   i n c i d e n c
e

Shobhit Mittal · Accepted Answer

<img alt="" src=
"https://s3mn%20mnimgs%20com/img/shared/content_ck_images/ck_5af1780032b52%20jpg">regards