Assertion: A spherical wavefront is produced by a point source of light. Reason: It is because, the locus of all points, which are equidistant from the point source, is a sphere.

Step-by-step solution

Huygens proposed that light is a longitudinal wave in the aether medium (-medium pervading the entire universe). The set of light particles (- “corpuscles” as called by Newton) oscillating in phase with each other is called a wavefront. Point sources give out spherical wavefronts, while sources at infinity give plane wavefronts. Hence, the assertion is true. The reason of these wavefronts to be sphere is because of the locus of points on wavefront which are equidistant from the point source. Thus, given