A) \[-75,\text{ }50\]
B) \[-10,15\]
C) \[75,\text{ }50\]
D) \[-15,10\]
Correct Answer: D
Solution :
Let focal length of convex lens is\[+f,\]then length of concave lens would be\[-\frac{3}{2}f\]. From the given condition \[\frac{1}{30}=\frac{1}{f}-\frac{2}{3f}=\frac{1}{3f}\] \[\therefore \] \[f=10\text{ }cm\] Therefore, focal length of convex lens\[=+10\text{ }cm\]and that of concave lens\[=-15\text{ }cm\].You need to login to perform this action.
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