A) 8cm
B) 12cm
C) 16 cm
D) 24cm
Correct Answer: A
Solution :
\[\frac{1}{f}=(\mu -1)\left( \frac{1}{R}+\frac{1}{\infty } \right)=\frac{0\cdot 5}{R}=\frac{1}{2R}\] But \[f=2R\] \[\therefore \] \[R=\frac{f}{2}=\frac{16}{2}=\mathbf{8}\]You need to login to perform this action.
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