question_answer

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

A)  \[{{1.43}^{o}}\]           

B)  \[{{0.72}^{o}}\]

C)  \[{{0.0125}^{o}}\]         

D)  \[{{0.025}^{o}}\]

Correct Answer: A

Solution :

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