The angle of a prism is A and if the angle of minimum deviation is 180 – 2A, then the refractive index of the material of the prism is:  


Correct option is

cot A/2






A ray of light suffers minimum deviation when incident on a 60o prism of refractive index  The angle of incidence is:


A ray is incident at an angle of incidence i on one face of a prism of small angle A and emerges normally from the opposite surface.  If the refractive index of the material of the prism is μ, the angle of incidence i is nearly equal to: 


The refracting angle of a prism is A and the refractive index of the prism is cot (A/2). The angle of minimum deviation is:  


A ray of light passes through an equilateral prism of glass in such a manner that the angle of incidence is equal to the angle of emergence and each of these angles is equal to (3/4) of the angle of prism. The angle of deviation is: 


If one face of a prism of prism angle 30o and  is silvered, the incident ray retraces its initial path. The angle of incidence is:


Angle of a prism is A and its one surface is silvered. Light rays falling at an angle of incidence of 2A on first surface return back through the same path after suffering reflection at the second silvered surface. Refractive index of the material is: 


An isosceles prism of prism angle 120o has a refractive index of 1.44. Two parallel monochromatic rays enter the prism parallel to each other in air as shown in figure. The rays emerging from the opposite faces: 



The angle of prism is 60o and its refractive index is 1.5. There will be no emergent light if the angle of incidence on the first face is: 


A glass prism of refractive index 1.5 is immersed in water (refractive index 4/3). A light beam incident normally on the face AB is totally reflected to reach the face AC if:  



An equilateral prism is placed on the prism table of a spectrometer in the position of minimum deviation. If the angle of incidence is 60o, the angle of deviation of the rays is: