Question

When a ray of light goes from one medium to another, there is
(a) Always a change in its speed as well as direction
(b) No change in speed and direction
(c) A change in speed but no change in direction
(d) A change in direction but constant speed. answer plzzz very urgent​

Answer 1

always a change in its speed as well as direction

Answer 2

Answer:

When a ray of light goes from one medium to another, there is always a change in its speed as well as direction i.e.option(A).

Explanation:

Speed of light

First, let's see the relationship between refractive index and speed of light in a particular medium,

$\mu=\frac{c}{v}$          (1)

Where,

μ=refarctive index of the medium

c=speed of light=$3\times10^8$ m/s    (constant)

v=speed of light in that medium

So as "c" is constant then we can write equation (1) as,

$\mu\propto \frac{1}{v}$         (2)

From equation (2) we can see that with the change of medium the speed of light also changes.

Direction of light

When a ray of light moves from rarer to a denser medium it bends towards the normal. And if the ray of light moves from denser to rarer medium it moves away from normal. So, with the change of medium, the direction of light also changes.

Hence, when a ray of light goes from one medium to another, there is always a change in its speed as well as direction i.e.option(A).