Question

with a concave mirror an object is placed at a distance x1 from the principal focus on the principal axis.its image is formed at a distance x2 from the principal focus.the focal length of the mirror is

Answer 1

1/v + 1/u = 1/f Using this formula you can calculate focal length. In this case, the focal length should be 2x/3

Answer 2

U = -(x1+f)

V= - ( x2+f)

1/v +1/u= 1/f

Substitute the values

f= root (x1 x2)