Question

A concave mirror forms a real image of magnification = 1 , if focal length of mirror is 15 cm then the position of object and position of image respectively are​

Answer 1

Answer:

as the image is real , magnification = -1

magnification = - v/u

that is,

-v/u = -1

that is, v = u

according to mirror formula,

1/v + 1/u = 1/f

substitute v=u

then, 1/u + 1/u = 1/f

as we have concave mirror, the focal length will be negative

so, focal length = -15cm

2/u = 1/-15cm

u = -15×2 cm = -30 cm

v = u

so, v = -30 cm

hence, position of image = position of object = 30 cm in front of the mirror