Question

with a concave mirror an object is placed at a distance X1 from the principal focus on the principal axis the image is formed at a distance X2 from the principal focus the focal length of the mirror is

Answer 1

Answer:

f=(X2×X1)/(X1-X2).

Explanation:

1/f=1/v-1/u

1/f=(u-v)/vu

f=(vu)/u-v

Here,

image distance v = X2

object distance u = X1

focal length f = ?

f=(X2×X1)/(X1-X2).

HOPE THIS ANSWER HELPS U.

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.