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∘ (j) convex (k) between pole and focus