Question

How is laws of reflected are followed in spherical mirrors?

Answer 1

The simpler method relies on two rules of reflection for concave mirrors. They are:

Any incident ray traveling parallel to the principal axis on the way to the mirror will pass through the focal point upon reflection.

Any incident ray passing through the focal point on the way to the mirror will travel parallel to the principal axis upon reflection.

Answer 2

◼️ Laws of Reflection and spherical mirrors

The 'Special properties' of spelling kar mirror are just an application of the laws of reflection. At every point, spherical mirror reflects an incident ray in such a way that the angle of reflection equals to the angle of incidence. [ Here, we have to remember that the normal, at the point of incidence, is simply the radius of the sphere (of which the given mirror is a part) at that point ].

If a ray is incident it in such a way that it passes through (or appears to pass through) the the focus of a spherical mirror, it becomes parallel to its principal axis, after reflection. A Ray directed towards the centre of curvature of a mirror retraces its path as it is incident normally on the mirror.

Now, note for the laws of spherical mirror are as follows :

• A Ray, parallel to the principal axis, passes through ( or appears to diverge from ) the the focus of the mirror, after reflection.

• A Ray, directed towards the focus of spherical mirror, becomes parallel to its principal axis, after reflection.

• A Ray, directed towards the centre of curvature of a spherical mirror, retraces its path after reflection.

( NOTE : The ray diagram is given in provided in attachment ).

We can use any two of these special race to obtain the details of the images (formed by spherical concave and convex mirrors) when the object is situated at different distances from the mirror.