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General
Easy
Question
Two planoconvex lenses each of focal length 10 cm & refractive index 3/2 are placed as shown. In the space left, water (R.I = 4/3) is filled. The whole arrangement is in air. The optical power of the system is (in diopters) :
- 6.67
- – 6.67
- 33.3
- 20
The correct answer is: 6.67
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