Question
The wavefront of a distant source of unknown shape is approximately:
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Answer
(a): plane
Explanation: When the point source or linear source of light is a very large distance, a small portion of the spherical or cylindrical wavefront appears to be plane. Such a wavefront is plane wavefront.
Explanation: When the point source or linear source of light is a very large distance, a small portion of the spherical or cylindrical wavefront appears to be plane. Such a wavefront is plane wavefront.
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