When light enters from air to water,then its

Monochromatic light of wavelength $589 \; nm$ is incident from air on a water surface. What are the wavelength,frequency,and speed of
$(a)$ reflected,and
$(b)$ refracted light? Refractive index of water is $1.33$.

Figures $(a)$ and $(b)$ show refraction of a ray in air incident at $60^{\circ}$ with the normal to a glass-air and water-air interface,respectively. Predict the angle of refraction in glass when the angle of incidence in water is $45^{\circ}$ with the normal to a water-glass interface [Figure $(c)$].

$A$ ray of light is incident at the glass-water interface at an angle $i$. It emerges finally parallel to the surface of water. If the refractive index of water is $\mu_w = 4/3$,then the value of the refractive index of glass $\mu_g$ is:

Give one example of a substance whose mass density is low but optical density is high.

The incorrect statement about the refractive index for a pair of media is: