For light diverging from a point source,
(a) The wavefront is spherical
(b) The intensity decreases in proportion to the distance squared
(c) The wavefront is parabolic
(d) The intensity at the wavefront does not depend on the distance

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Vishal Baghel | Contributor-Level 10

7 months ago

This is a Multiple Choice Questions as classified in NCERT Exemplar

Answer- (a, b)

Explanation- Due to the point source light propagates in all directions symmetrically and hence, wavefront will be spherical as shown in the diagram.

If power of the source is P, then intensity of the source will be I= p

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For light diverging from a point source,(a) The wavefront is spherical(b) The intensity decreases in proportion to the distance squared(c) The wavefront is parabolic(d) The intensity at the wavefront does not depend on the distance