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General
Easy
Question
A symmetrical converging convex lens of focal length 10 cm & diverging concave symmetrical lens of focal length - 20 cm are cut from the middle and perpendicularly and symmetrically to their principal axis. The parts thus obtained are arranged as shown in the figure. The focal length of this arrangement will be:
- 20 cm
- 40 cm
- 80 cm
The correct answer is: 80 cm
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