question_answer

(a) Define the following terms in the context of spherical mirrors:                                           [5]

(i) Pole

(ii) Centre of curvature

(iii) Principal axis

(iv) Principal focus

(b) Draw ray diagrams to show the principal focus of a:

(i) Concave mirror

(ii) Convex mirror

(c) Consider the following diagram in which M is a mirror and P is an object and Q is its magnified image formed by the mirror.

State the type of the mirror M and one characteristic property of the image Q.

Answer:

(a) (i) Pole is the centre of the reflecting surface of the mirror.

(ii) Centre of curvature is the centre of the hollow sphere of which the reflecting surface of mirror is a part.

(iii) Principal axis is the straight line passing through the pole and the centre of curvature of a spherical mirror.

(iv) Principal focus: Incident rays parallel to principal axis, after reflection, either converge to or appear to diverge from a fixed point on the principal axis called principal focus of a spherical mirror.

(b) (i)

(ii)

(c) M is a concave mirror and the image is virtual.