Question

find the focal lenght of a concave mirror​

Answer 1

Explanation:

The focal length of a concave mirror can be found using following method:

We can put an object far away from the concave mirror and place a screen to obtain the image formed. The place where the image formed is sharpest is the focus of the mirror. By measuring the distance between the focus and mirror, we get the focal length.

Answer 2

Answer:

Focal length of a concave mirror

Explanation:

Focal length of a concave mirror is a point on the principal axis where the light rays parallel to the principal axis after reflection converge or diverge towards it

A CONCAVE MIRROR HAS FOCAL LENGHT ALWAYS NEGATIVE

-> concave mirrors are commonly called converging mirrors

Hope it helps!