A cardsheet divided into squares each of size `1 mm^(2)` is being viewed at a distance of `9 cm` through a magnifying glass (a conerging lens of focal length `10 cm`) held close to the eye.
(a) What is the magnification produced by the lenas ? How much is the area of each square to the virtual image ?
(b) What is the angular magnification (magnifying power) of the lens ?
( c) Is the magnification in (a) equal to the magnifying power in (b) ? Explain

Options

A. `1cm^2`
B. `0.81cm^2`
C. `0.27^2`
D. `0.60cm^2`

Answer

A

Explanation

`u=-9cm,f=10cm`
`(1)/(v)-(1)/(u)=(1)/(f)implies(1)/(v)-(1)/(-9)=(1)/(10)`
`(1)/(v)=(1)/(10)-(1)/(9)=(-1)/(90)`
`v=-90cm`
`m=(v)/(u)=(-90)/(-9)=10`
`(A_i)/(A_O)=m^2implies(A_i)/(I)=(10)^2`
`A_i=100m^2=1cm^2`