Light travels more quickly through water than through glass. (a) Which is optically denser : water or glass ? (b) If a ray of light passes from glass into water, which way will it bend : towards the normal or away from the normal ?

Q. A ray of light travelling in water enters obliquely into glass. Does the light ray bend towards or away from the normal? Why?

Q. What happens when light ray passes through a glass slab?

Q. If a ray of light goes from a denser medium to a rarer medium, will it bend towards the normal or away from the normal?

Q.

Fill in the blanks :

(a) Water is optically ___ than air.

(b) Air is optically ___ than glass.

(c) When a ray of light travels from water to air, it bends ___ the normal.

(d) When a ray of light travels from air to glass, it bends ___ the normal.

(e) When white light passes through a prism, it ___

(f) The splitting of white light into its constituent colours is called ___

(g) A ___ mirror is obtained on silvering the outer surface of a part of a hollow glass sphere.

(h) Radius of curvature of a spherical mirror is ___ its focal length.

(i) The angle of incidence for a ray of light passing through the centre of curvature of aspherical mirror is ___

(j) A ___ mirror always forms a virtual image.

(k) A concave mirror forms a virtual image for an object placed ___

Ans. (a) denser (b) rarer (c) away from (d) towards (e) disperses (f) dispersion

(g) concave (h) two times (i) $0^{\circ }$ (j) convex (k) between pole and focus

Q. As light rays pass from air into a glass prism, are they refracted towards or away from the normal?