Physics
Explain the meaning of the terms focus and focal length in case of a convex mirror, with the help of a suitable ray diagram.
Answer
Focus of a convex mirror — The focus of a convex mirror is a point on the principal axis from which, the light rays that are incident parallel to the principal axis, appear to come, after reflection from the mirror.
Focal length of a convex mirror — The distance of focus F from the pole P of the convex mirror is called the focal length of the convex mirror.
i.e., focal length f = PF.
Related Questions
(i) Name the mirrors shown in figure (a) and (b).
(ii) In each case (a) and (b), draw the reflected rays for the given incident rays and mark focus by the symbol F.
Draw suitable diagrams to illustrate the action of (i) concave mirror, and (ii) convex mirror, on a beam of light incident parallel to the principal axis.
Complete the following diagrams shown in figure by drawing the reflected ray for each of the incident ray A and B.
Complete the following diagrams in figure by drawing the reflected rays for the incident rays 1 and 2.
