Question

The angle subtended by a coin of radius $1cm$ held at a distance of $80cm$ from your eyes is

• A. $1.43^{\circ }$
• B. $0.72^{\circ }$
• C. $0.0125^{\circ }$
• D. $0.025^{\circ }$

Answer 1

Answer: (A)

Let angle subtended by coin at the eye be $6$.
$\sin \theta \simeq \frac{D}{L}$
Here, $D=2r=2\times 1=2cm$
$L=80cm$
$\therefore$ $\theta =\frac{2}{80}=0.025$ rad
$=1.43^{\circ }$