A) 0.1m
B) 0.75m
C) 0.4m
D) 0.2m
Correct Answer: D
Solution :
[d] After silvering the plane surface, piano convex lens behaves as a concave mirror of focal length \[\frac{I}{{{f}^{'}}}=\frac{2}{{{f}_{lens}}}\] \[{{f}^{'}}=0.2m{{f}_{lens}}=2\times 0.2=0.4m\] from lens maker formula \[\frac{1}{{{f}_{lens}}}=(\mu -1)\left[ \frac{1}{{{R}_{1}}}-\frac{1}{{{R}_{2}}} \right]\] \[\frac{1}{0.4}=(1.5-1)\times \frac{1}{{{R}_{1}}}[{{R}_{2}}=\infty ]\] \[{{R}_{1}}=0.5\times 0.4\] \[{{R}_{1}}=0.2m\]You need to login to perform this action.
You will be redirected in
3 sec