Question

1. Define the term 'principal focus' in case of a convex mirror​

Answer 1

Answer:

The light rays that converge on the principal axis after reflecting from a convex mirror and are parallel to the principal axis are called principal focus of a convex mirror. They either actually in real meets or appears virtually to meet.

Answer 2

Answer:

Here P is the principal axis of the convex mirror and the point R is the centre of curvature or the radius of the mirror. Now the light rays , which r parallel to the P , when falls on the mirror , the reflected rays reflect in a certain direction. Now , if we try to draw those reflected rays as a straight line by extending them to the backside of the mirror, they seem to converge at a point on the P. This is called the Principal Focus or only 'Focus' and is the half of the length of the radius.

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