REFRACTION OF LIGHT AND LAWS OF REFLECTION ||

STATEMENT -1 : If reflected or refracted ray diverge from a point, the image will be virtual. and STATEMENT - 2 : After reflection or refraction the refracted or reflected rays appear to meet at a point on principle axis. They do not actually meet at a point.

A parallel beam of light of intensity I is incident on a glass plate. 25% of light is reflected in any reflection by upper surface and 50% of light is reflected by any reflection from lower surface. Rest is refracted The ratio of maximum to minimum intensity in interference region of reflected rays is

Let the refractive index of a denser medium with respect to a rarer medium be n_(12) and its critical angle be theta_(c) . At an angle of incidence A when light is travelling from denser medium to rarer medium, a part of the light is reflected and the rest is refracted and the angle between reflected and refracted rays is 90^(@) , Angle A given by -

Let the refractive index of a denser medium with respect to a rarer medium be n_(12) and its critical angle be theta_(c) . At an angle of incidence A when light is travelling from denser medium to rarer medium, a part of the light is reflected and the rest is refracted and the angle between reflected and refracted rays is 90^(@) , Angle A given by -

When light is polarised by reflection from a transparent surface. a) reflection and refracted rays are mutually perpendicular b) both reflected and refracted rays are plane polarised c) refraction ray is partially polarised d) the R.I., of transparent surface is equal to tangent of Brewster.s angle

A light ray is travelling from air to glass. True reflected and refracted rays are perpendicular to each other. If the angle of incidence in air is I the refractive index of glass is

Assertion : The rainbow is an example of the dispersion of sunlight by the water drops in the atmosphere. Reason : No reflection or refraction of light is involved in the formation of rainbow.

(a) State Huygen's principle . Using this principle draw a diagram to show how a plane wave front incident at the interface of the media gets refracted when it propagates from a rarer to a denser medium. Hence verify Snell's law of refraction. (b) When monochromatic light travels from a rarer to a denser medium, explain the following, giving reasons- (i) Is the frequency of reflected and refracted light same as the frequency of incident light? (ii) Does the decrease in speed imply a reduction in the energy carried by light wave?