$A$ prism with a refractive index of $1.53$ is placed in water with a refractive index of $1.33$. If the angle of the prism is $60^{\circ}$,then the angle of minimum deviation in water will be ....$^{\circ}$.

The ratio of the angle of minimum deviation of a prism in air to that when it is dipped in water is (given $_a\mu_g = 3/2$ and $_a\mu_w = 4/3$).

Consider an equilateral prism (refractive index $ \sqrt{2} $). $A$ ray of light is incident on its one surface at a certain angle $ i $. If the emergent ray is found to graze along the other surface, then the angle of refraction at the incident surface is close to . . . . . . . (in $^{\circ}$)

If the refractive angles of two prisms made of crown glass are $10^o$ and $20^o$ respectively,then the ratio of their angular dispersions will be

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 return back through the same path after suffering reflection at the silvered surface. The refractive index $\mu$ of the prism is:

One face of the glass prism is silver polished. $A$ light ray falls at an angle of $45^{\circ}$ on the other face. After refraction,it is subsequently reflected from the silvered face and then retraces its path. The refracting angle of the prism is $30^{\circ}$. The refractive index of the prism is