Question

The human eye has an approximate angular resolution of $\theta=5.8 \times 10^{-4}$ rad and typical photo printer prints a minimum of $300$ dip (dots per inch, 1 inch $=2.54 $ cm ). At what minimal distance $d$ should a printed page be held so that one does not see the individual dots?

• A. 20.32 cm
• B. 29.50cm
• C. 14.59 cm
• D. 6.85 cm

Answer 1

Answer: (C)

$\theta=\frac{x}{d} $
$5.8 \times 10^{-4}=\frac{2.54}{300} \times \frac{1}{d} $
$ d=14.59\, cm$
$\theta=\frac{x}{d} $
$5.8 \times 10^{-4}=\frac{2.54}{300} \times \frac{1}{d}$
$d=14.59\,cm$