Question

The distance of an object from the focus of a concave mirror of focal length 'f' is 'x' and the distance of real image from the focus is 'y' then​

Answer 1

Answer:

According to Newton 's mirror relation,

cc' = f

2

where c is object distance and c' is image distance, both from focus

Thus as per given question, f= in root xy

Answer 2

The distance between the pole P of the concave mirror and the focus F is the focal length of the concave mirror. Thus, the focal length of a concave mirror can be estimated by obtaining a 'Real image' of a distant object at its focus, as shown in the figure.