At a very large distance from a point source we get:
Correct answer: C. A plane wave front
- A. An elliptical wave front
- B. A cylindrical wave front
- C. A plane wave front
- D. A rectangular wave front
Explanation
Far from a point source (large radius of curvature), the spherical wavefront locally approximates a plane wavefront, so waves appear planar to distant observers.
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About Optics
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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