Geometrical OpticsHard

Question

An isoscales prism of angle 120o has a refrective index 1.44. Two parallel rays of monochromatic light enter the prism parallel to each other in air as shown. The rays emerging from the opposite face
       

Options

A.are parallel to each other
B.are diverging
C.making an angle 2 [sin-1 (0.72) -30o] with each other
D.making an angle 2 sin-1 (0.72) with each other

Solution

           
The diagramatic representation of the given problem is shown in figure
From figure it follows that ∠i = ∠A = 30o
From Nell′s law n1 sin i = n2 sin r
or       sin r = = 0.72
Now, ∠δ = ∠r - ∠i = sin-1 (0.72) - 30o
∴ θ = 2(∠δ) = 2 {sin-1(0.72) - 30o}.

Create a free account to view solution

View Solution Free
Topic: Geometrical Optics·Practice all Geometrical Optics questions

More Geometrical Optics Questions