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

The angle of a prism is A. One of its refracting surfaces is silvered. Light rays falling at an angle of incidence 2A on the first surface re turns back through the same path after suffer ing reflection at the silvered surface. The re fractive index m of the prism is

The angle of a prism is A . One of its refracting surfaces is silvered. Lihgt rays falling at an angle of incidence 2A on the first surface returns back through the same path after suffering reflection at the silvered surface. The refractive index. mu , of the prism is

The angle of a prism is A . One of its refracting surfaces is silvered. Lihgt rays falling at an angle of incidence 2A on the first surface returns back through the same path after suffering reflection at the silvered surface. The refractive index. mu , of the prism is

The angle of a prism is A , One of its refracting surface is slivered . Light rays falling at an angle of incidence 2A on the first surface returns back through the same pathe after suffering reflection at the silvered surface. The refractive index mu of the prism is:

An isosceles prism of angle A=30^(@) has one of its surfaces silvered. Light rays falling at an angle of incidence 60^(@) on the other surface retrace their path after reflection from the silvered surface. The refractive index of prism material is