question

a triangular prism of refracting angle  is made of a transparent material of refractive index  . a ray of light is incident normally on the face kl as shown in the figure. trace the path of the ray as it passes through the prism and calculate the angle of emergence and angle of deviation.

 

 

 

 

 

 

 

the refracting angle is 

since at first face ray does not deviate,

therefore

applying snells law at second face

hence, , is the angle of emergency,

so the angle of deviation is equal to .