00:01
Hi, here in this given problem this is the prism having the apex angle phi.
00:13
This angle is given as phi.
00:16
Now the angle of incidence for the ray of light entering into the prism, this is the ray of light.
00:27
Then its first angle of incidence that is theta 1, then it goes like this at an angle of refraction then another angle of incidence at the opposite face of the prism then it goes out to the other side making another angle of refraction so if we look for the angles this is the angle of incidence theta 1 then the angle of incidence this 3 angle of refraction this is theta 2 and angle of refraction this is theta 4 so here we have to obtain a relation among the angles of refraction means theta 2 and theta 3 and there's some we have to prove it to be equal to the apex angle 5.
01:49
So here this angle between the normals drawn at the faces refracting surfaces of the prism.
01:59
Suppose this angle to be given as x, angle x.
02:05
This is point a, this is point b, here this is c and suppose this point to be d.
02:13
In triangle b, c, d, in triangle b, c, d, using angle sum relation angle theta 2 plus angle x plus angle theta 3 that should come out to be equal to 180 degree and we consider it to be equation number 1 then in quadrilateral a b c d here this angle will be 90 degree as these are the normals this angle will also be 90 degree so, we can say angle a plus at point b, this is angle 90 degree plus angle x at c plus one more 90 degree...