A) \[\frac{10}{3}\,\,cm\]
B) 30 cm
C) 15 cm
D) \[\frac{100}{3}\,\,cm\]
Correct Answer: B
Solution :
For improving far point, concave lens is required and for this concave lens \[u=\infty ,\,\,\nu =-30\,cm\] So, \[\frac{1}{f}=\frac{1}{-30}-\frac{1}{\infty }\,\,\,\,\,\,\,\Rightarrow \,\,\,f\,\,=\,\,-\,30\,cm\] For near point \[\frac{1}{-30}=\frac{1}{-50}-\frac{1}{u}\,\,\,\,\,\,\,\Rightarrow \,\,\,u\,\,=\,\,-\,30\,cm\]You need to login to perform this action.
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