In an equilateral prism,the ray undergoes minimum deviation when it is incident at an angle of $50^{\circ}$. The angle of minimum deviation is (in $^{\circ}$)

The angle of minimum deviation for an incident light ray on an equilateral prism is equal to its refracting angle. The refractive index of its material is

$A$ ray of light incident on one face of an equilateral glass prism having refractive index $\sqrt{2}$, produces the emergent ray which just grazes along the adjacent face. The value of angle of incidence is $(\sin 90^{\circ} = 1, \sin 30^{\circ} = 0.5, \sin 45^{\circ} = 1/\sqrt{2})$.

$A$ thin prism $P_1$ with angle $4^o$ made of glass of refractive index $1.54$ is combined with another thin prism $P_2$ made of glass of refractive index $1.72$ to produce no deviation. The angle of prism $P_2$ is.....$^o$

The refraction through the prisms is as shown. Pick out the wrong statement from the following. Path of the light ray in

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