A child has near point at `10 cm`. What is the maximum angular magnification the child can have with a convex lens of focal length `10 cm` ?

Explanation

For maximum angular magnification,
`v = -d = -10 cm`
From `(1)/(v)-(1)/(u)=(1)/(f),(1)/(u)=(1)/(v)-(1)/(f)=-(1)/(10)-(1)/(10)=-(1)/(5)`
`u = -5 cm`
Maximum angular magnification,
`m = (v)/(u)=(-10)/(-5) = 2`.