Two coherent monochromatic light beams of intensities I and 4I are superposed. The maximum and minimum possible intensities in the resulting beam are;
Correct answer: C. 9I and I
- A. 5I and I
- B. 5I and 3I
- C. 9I and I
- D. 9I and 3I
Explanation
Amplitudes ∝ √I. Max intensity Imax = (√I + √4I)² = (1+2)² I = 9I. Min intensity Imin = (1−2)² I = 1 I. Thus extremes are 9I and I.
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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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