A) 5/4
B) \[\sqrt{3}\]
C) 4/3
D) 5/3
Correct Answer: D
Solution :
Focal length of lens \[{{f}_{a}}=\frac{100}{P}\] \[=\frac{100}{5}=20cm\] Focal length of lens in liquid \[{{f}_{1}}=100cm\] from the formula \[\frac{{{f}_{1}}}{{{f}_{a}}}=\frac{{{(}_{a}}{{n}_{g}}-1)}{\left( \frac{_{a}{{n}_{g}}}{_{e}{{n}_{1}}}-1 \right)}\] \[-\frac{100}{20}=\frac{(1.5-1)}{\left( \frac{1.5}{x}-1 \right)}\] \[-5=\frac{0.5}{\left( \frac{1.5}{x}-1 \right)}\] \[\Rightarrow \] \[\frac{1.5}{x}-1=-0.1\,\,\,\,\,\,\,\frac{1.5}{x}=0.9\] \[x=\frac{15}{9}=\frac{5}{3}\]You need to login to perform this action.
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