A) Disappear
B) Remain as real image still
C) Be virtual and of the same size as the object
D) Suffer from aberrations
Correct Answer: C
Solution :
\[\frac{1}{f}=(\mu -1)\left( \frac{1}{{{R}_{1}}}-\frac{1}{{{R}_{2}}} \right)\] For biconvex lens \[{{R}_{2}}=-{{R}_{1}}\] \[\therefore \] \[\frac{1}{f}=(\mu -1)\left( \frac{2}{R} \right)\] Given \[R=\infty \] \[\therefore \] \[f=\infty \], so no focus at real distance.You need to login to perform this action.
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