Light travelling in air falls at an incidence angle of `2^(@)` on one rafracting surface of a prism of refractive index `1.5` and angle of refraction `4^(@)`. The medium on the other side is water `(n=4//3)` . Find the deviation produced by the prism.

Answer

`1^(@)`

Explanation

we can use `sin x = x` (where `x` is in radians)
`sin i =(3)/(2) sin r_(1) rArr i=(3)/(2) r_(1) rArr2^(@) xx(pi)/(180^(@))=(3)/(2)xx(pi)/(190^(@))xxr_(1)^(@)`
`rArr r_(1)=(4^(@))/(3),rArrr_(2)=A-r_(1)=(8^(@))/(3)`
`therefore (3)/(2) sinr_(2)=(4)/(3) "sine" rArr ɵ (9)/(8)r_(2)=3^(@)`
`therefore delta=i+e-A=2^(@)+3^(@)-4^(@)=1^(@)`