Question #cf067

1 Answer
Dec 12, 2016

We know the lens formula as follows

1/v+1/u=1/f

where

u->"object distance"=-ve

v->"imsge distance"=+ve

m->"magnification"=-1

color(red)"since real image is formed"

"Now " v/u=m=1=>v=-u=

f->"focal length"=f" for convex lens"

So the above equation becomes

-1/u-1/u=1/f

=>u=-2f

Hence it is possible when

color(blue)("object distance"(u) = 2xx"focal length"(f))