A real object is placed at a distance f from the pole of a convex mirror, in front of the convex mirror. If focal length of the mirror is f, then distance of the image from the pole of the mirror is ........

Options

A. `f/2`
B. `f/4`
C. `2f`
D. `4f`

Answer

A, B

Explanation

f is positive for convex mirror
`therefore 1/f=1/u+1/v`
`therefore 1/f=(1)/(-f)+(1)/(v)` (by u=-f)
`therefore 1/f+1/f=1/v`
`therefore2/f=1/v`
`therefore v=f/2`