A convex and concave lens of focal length 'f' are in contact; the focal length of the combination will be
Correct answer: B. f/2
- A. Zero
- B. f/2
- C. 2f
- D. Infinite
Explanation
When a convex and concave lens of equal focal lengths are in contact, the combined lens has a focal length equal to half of the individual focal lengths. Therefore, the focal length of the combination is f/2.
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Light is studied through reflection, refraction, dispersion, interference, diffraction and polarization, linking ray behavior with its wave nature. Questions may involve mirrors, lenses, optical instruments, refractive index and image formation, while geometrical optics deals with rays and wave optics explains effects such as interference and diffraction.
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