Light in a variable slab!
A light way enters from air inside a slab as shown in the figure below. If the width of the slab is very large, then find the maximum possible -coordinate of the light ray (in meters).
Give your answer to 2 decimal places.
The answer is 1.0000.
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1 solution
It is similar to a JEE question of 1999 on optics. First write Snell's law, s i n ( 3 0 ⋅ ) = ( 1 . 5 − y ) ( s i n ( i ) ) Then draw an approximate path travelled by light. From this we can see that, d y / d x = c o t ( i ) Then substitute the values and find max of y by usual methods.