convex lens of power 4 diopter is combined with a concave lens of power 3 diopter. The combination will behave as:
Correct answer: D. Convex lens of 1m focal length
- A. Concave lens of 0.5m focal length
- B. Convex lens of 0.5m focal length
- C. Concave lens of 1m focal length
- D. Convex lens of 1m focal length
Explanation
Power of the lensP = P1 + P2P1 =4 (convex lens)P2 = -3 (concave lens)P = 4-3P = 1Focal length = Focal length = 1 (The positive power indicates that the combined sysytem is behaving as convex lens)
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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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