Question

Solve No. 3 :)

Kindly Give a proper explanation !

#No spams
#No short answers​

Answer 1

Answer:

a.i) When a ray of light passing through the centre of curvature of a concave mirror reflects back along the same path, without any deviation.

ii) In case of a convex mirror, an incident ray which appears to move towards the centre of curvature is reflected back along the same path without any deviation.

Answer 2

3) a)

(i) A ray of light passing through the centre of curvature of a concave mirror is reflected back along the same path because it strikes the concave mirror at right angles to its surface due to which the angle of incidence and angle of reflection both are O.

(see attachment f1st)

(ii) Focal length of concave mirror: The distance between pole and principal focus.

Rule 1: When a ray of light which is parallel to the principal axis gets reflected, it passes through its focus.

Rule 2: When a ray of light passes through the centre of curvature, it gets reflected back along the same path.

(see attachment 2nd)

b)

Light rays from infinity, which are parallel to the principal axis of a concave mirror, converge at the the principal focus (F) after reflection from the mirror.

(see attachment 3rd)