What should be the distance between the object and magnifying glass if the virtual image of each square in the figure is to have an area of `6.25 mm^(2)`.Would you be able to see the squares distinctly with your eyes very close to the magnifier ?

Explanation

Magnifies area of each square `=6.25mm^(2)`
Linear magnification,
`m=(sqrt(6.25))/(1)=2.5`
`"Also, "m=(v)/(u)`
`therefore" "(v)/(u)=2.5`
`v=+2.5u`
Using the relation,
`(1)/(v)-(1)/(u)=(1)/(f)`
`(1)/(2.5u)-(1)/(u)=(1)/(10)`
`u=-6cm`
`therefore" "v=2.5xx6=-15cm`
The virtual image is closer than the normal near point (25 cm) and cannot be seen by the eye distinctly.