Question

What is refraction??!!!​

Answer 1

Refraction

Refraction is the bending of the light away or towards the normal of the surface of interface

while moving from one transparent medium to another transparent medium

Case 1 :

When light travels through rarer medium to denser medium, the refracted ray bend towards the normal

Case 2 :

When light travels through denser medium to rarer medium, the refracted ray bend away from the normal

Laws of refraction of light

• The incident ray, the refracted ray and the normal to the interface of two transparent media at the point of incidence, all lie in the same plane
• The ratio of sine of angle of incidence to the sine of angle of refraction is a constant, for the light of the given colour and the given media. This is also known as Shell's law

Sin I/ Sin R = Constant

Answer 2

Answer:

REFRACTION

$When \: a \: light \: travels \: from \: one \\ transparent \: medium \: to \: other, \\ it \: deviates \: from \: its \: original \: path. \\ The \: phenomenon \: of \: change \: in \\ path \: of \: light \: at \: the \: medium \: of \\ separation \: as \: it \: goes \: from \: one \\ medium \: to \: other \: medium \: is \\ called \: as \: refraction.$

Snell’s  Law  :

1. The incident ray, the refracted ray and the normal to the interface at the point of incidence, all lie in the same plane.

2. The bending of light at the medium of separation follows Snell's law. In the figure if NN' represents normal at the medium of separation and ‘i ' and ‘r ' are the angles of incidence and refraction respectively then for pair of media and for a given colour $\frac{sin \:i}{sin \:r} = \dfrac{\mu_{1}}{\mu_{2}}=Constant$

$=> \frac{sin\: i}{sin\: r} = \frac{\mu_{2}}{\mu_{1}} \\ _{1}\mu_{2} \: is \: called \:as\: refractive \:index \:of \\ second \:medium \: w.r.t \: first \:medium$

$\mu_{2} \: and \: \mu_{1}$ are the absolute refractive indices of rarer and denser medium.

Hence, in the first case$\mu_{1}sin\: i = \mu_{2}sin \:r$ and in the second case $\mu_{2}sin\: i = \mu_{1}sin \:r$ are applicable. When light ray travels from rarer to denser media it bends towards normal and when it travels from denser to rarer media it bends away from normal.