What will be the angle of refraction for a light ray incident normally at the surface (in $^{\circ}$)?

$A$ light ray enters from medium $A$ to medium $B$ as shown in the figure. The refractive index of medium $B$ relative to $A$ will be

When does Snell's law fail?

Define absolute refractive index. Absolute refractive indices of medium $A$ and medium $B$ are $n_{a}$ and $n_{b}$ respectively. What is the refractive index of medium $B$ with respect to medium $A$? How does the velocity of light vary with change in the optical density of the media?

If the absolute refractive indices of water, benzene, and sapphire are $1.33$, $1.50$, and $1.77$ respectively, then which medium has the maximum relative refractive index?

You are given kerosene,turpentine,and water. In which of these does the light travel fastest? Use the information given in the table below.

Material medium	Refractive index
Water	$1.33$
Kerosene	$1.44$
Turpentine oil	$1.47$