If f1 = 12 cm, f2 = -18 cm, find the maximum focal length of the combination.
Correct answer: A. 36 cm
- A. 36 cm
- B. 34 cm
- C. 32 cm
- D. 30 cm
Explanation
To find the maximum focal length of the combination, we use the formula 1/f = 1/f1 + 1/f2. Substituting the given values f1 = 12 cm and f2 = -18 cm, we get 1/f = 1/12 + 1/-18. Solving this equation gives us f = 36 cm. This means the maximum focal length of the combination is 36 cm. The other options are incorrect because they do not correctly apply the formula or contain calculation errors.
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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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